ALBERT

Notes: Professor F. Ackermann was specially invited to contribute an article to mark the 50th issue of The Photogrammetric Record. As the only photogrammetrist to have received both the Brock and von Gruber awards of the International Society for Photogrammetry, he is particularly well qualified to express his views on the past and future development of photogrammetry.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméLe professeur Ackermann a été invitéàécrire un article pour fêter la sortie du 50ème numéro. Seul photogrammètre cumulant médaille de Brock et médaille de von Gruber, il était particulièrement qualifié pour juger du passé et préjuger de l'avenir de la photogrammétrie.〈section xml:id="abs1-3"〉〈title type="main"〉Zusammenfassung Professor Ackermann wurde gezielt eingeladen, um einen Beitrag anlässlich des Erscheinens der 50. Ausgabe des Photogrammetric Record beizusteuern. Als einziger Photogrammeter, der sowohl den Brock- als auch v. Gruber-Preis der ISP erhalten hat, ist er besonders qualifiziert, seine Ansichten über Vergangenheit und Zukunft der Photogrammetrie zu äussern.

Notes: The author describes his experiences of working with Professor E. H. Thompson on the design and construction of the Thompson-Watts plotter and he relates several anecdotes of incidents which took place at the Hilger and Watts factory.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOù on décrit l'expérience d'années passées à travailler avec le professeur Thompson sur le projet du restituteur Thompson- Watts avec de nombreuses anecdotes sur la vie à l'usine Hilger and Watts.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungDer Autor schreibt über seine Erfahrungen, die er bei der Zusammenarbeit mit Professor E. H. Thompson beim Entwurf und der Konstruktion des Thompson–Watts-Plotters sammelte. Er erwähnt dabei einige Anekdoten über Vorfälle, die sich bei der Firma Hilger und Watts ereigneten.

Notes: A history and analysis of stereoplotting instrument design and construction in the United Kingdom is given, beginning with the earliest instruments of F. V. Thompson dating from 1907 and 1908 and covering all known designs up till the late 1960s. In the first part of the paper, the instruments built in the 1920s and 1930s are described, much new information having come to light recently in the archives of Ban and Stroud Ltd. and in the papers of the late Professor E. H. Thompson. In the second part of the paper, the instruments which were produced during and after the Second World War are discussed in detail, with an emphasis on those designs which are less well known rather than those which were produced in quantity. The ideas and designs of Deville, F. V. Thompson, Fourcade and E. H. Thompson have been the dominating influences throughout the period and a strong thread of continuity can be established between them.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn fait l'histoire du restituteur analogique en Grande Bretagne, depuis ses balbutiements (F. V. Thompson 1907–1908), jusq'aux années 60. On décrit en particulier les appareils conçus dans les années 20 et 30, en tenant compte d'une masse d'informations inconnues à ce jour tirées des archives de M. Barr et Stroud, et de celles de feu le professeur Thompson. Puis on passe à ceux qui ont été produits pendant et après la guerre, en s'attachant surtout à ceux qui sont moins connus parce que n'ayant pas été produits en série. Ce sont les idées et projets de Deville, F. V. Thompson, Fourcade et E. H. Thompson qui ont dominé cette période, et le fil qui les relie reste très perceptible.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungEs wird ein Überblick und eine Analyse über den Entwurf und die Konstruktion von Stereoauswertegeräten im Vereinigten Königreich gegeben, wobei der Autor, beginnend mit den ersten Geräten von F. V. Thompson aus den Jahren 1907 und 1908 alle bekannten Entwürfe bis Ende der 60iger Jahre behandelt. Im 1. Teil werden die Geräte der 20iger und 30iger Jahre beschrieben, wobei viel neue Informationen aus dem Archiv der Firma Barr und Stroud und den Beiträgen des verstorbenen Professor E. H. Thompson entstammen. Im 2. Teil werden die während des 2. Weltkrieges und danach produzierten Geräte diskutiert, wobeisolche hervorgehoben werden, die weniger bekannt wurden als die in grossen Stückzahlen produzierten. Die Ideen und Entwürfe von Deville, F. V. Thompson, Fourcade, E. H. Thompson hatten einen bedeutenden Einfluss während dieser Zeit, und es kann eine starke kontinuierliche Verbindung zwischen ihnen aufgezeigt werden.

Notes: The development of remote sensing techniques for land use studies is briefly reviewed and some problems of interpretation of aerial and satellite photography considered. The need for a ground based data collection system is indicated and a prototype system developed at the University of Bristol is described. Some preliminary results obtained with this system are presented.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn passe en revue les progrès des techniques de télédétection en matière d'étude des sols et on examine certains problèmes d'interprétation des photographies aériennes et satellitaires. On insiste sur la nécessite d'établir une banque de données pour l'interprétation; on décrit le prototype qu'on met au point à l'université de Bristol, et certains résultats qu'il a déjà permis d'obtenir.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungDie Entwicklung der Fernerkundungsverfahren für Landnutzungsstudien wird kurz eingeschätzt und einige Probleme der Interpretation von Luftbildern und Satellitenphotos werden analysiert. Dabei wird die Notwendigkeit zur Schaffung eines Datenerfassungssystems im Gelände aufgezeigt und ein Prototyp eines solchen Systems, das an der Universität Bristol entwickelt wurde, beschrieben. Einige hiermit erhaltene vorläufige Ergebnisse werden angegeben.

Notes: The fourth biennial symposium of the Photogrammetric Society was held at the University of Birmingham on 22nd to 24th April and was dedicated to the memory of the late Professor E. H. Thompson. Nine papers were delivered. The first three were concerned with the life and work of Professor Thompson. Other speakers dealt, in turn, with future instrumentation in photogrammetry; aerial triangulation and film stability; photomaps and tests related to the perception of map users; map revision; and the recording of archaeological information. The majority of the papers are published in this issue of The Photogrammetric Record.〈section xml:id="abs1-2"〉〈title type="main"〉Résumé Le quatrième symposium biannuel de la Photogrammetric Society s'est tenu à l'université de Birmingham du 22 au 24 avril et était dédiéà la mémoire de feu le professeur Thompson. Il y eut neuf exposés, dont les trois premiers portaient sur la vie et l'oeuvre du défunt. D'autres orateurs traitèrent: de l'évolution prévisible des appareillages en photogrammétrie; de l'aérotriangulation et de la stabilité des films; des photoplans et de la manière dont Us sont accueillis par les utilisateurs de cartes; de la révision; et des cartes archéologiques. On trouvera ici la plupart de ces exposés.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungDas 4. alle zwei Jahre stattfindende Symposium der Britischen Photogrammetrischen Gesellschaft wurde vom 22. bis 24. April an der Universität Birmingham durchgeführt und war dem Gedenken an Professor E. H. Thompson gewidmet. Insgesamt wurden 9 Vorträge gehalten. Die ersten 3 befassten sich mit dem Leben und Wirken von Professor Thompson. Andere Referenten behandelten: künftige photogrammetrische Geräte, Aerotriangulation und Filmstabilität, Kartenergänzung, Bildkarten und Tests über die Auffassung der Kartennutzer, Aufzeichnung archäologischer Informationen. Die Mehrzahl der Beiträge wird im vorliegenden Heft veröffentlicht.

Notes: SYNOPSIS. Cortical ultrastructure of the scuticociliates Dexiotricha media and Dexiotricha colpidiopsis was investigated. The following elements of the somatic cortex were studied: the cell membrane, alveolar membranes and the epiplasm, kinetodesmal fibers, postciliary and transverse microtubular ribbons, and transverse fibers associated with single and paired kinetosomes; mitochondria and single microtubules located in interkinetal ridges; mature and early extrusion stages of mucocysts: the expulsion vacuole pore and tube, the nephridioplasm and the cytoproct. In the buccal cortex, the paroral kinety-ribbed wall complex, the 3 polykineties, and the cytostome-cytopharynx were investigated.Comparative survey of ciliate ultrastructure indicates 2 principal orientation patterns for kinetodesmal and postciliary fibers, recognition of which leads to reevaluation of the theory of paroral kinety formation and the ideas of homology based on this theory. Ultrastructurally, the scuticociliates are not distinct from tetrahymenines and peniculines; the 3 groups appear to be 1 assemblage.

Notes: SYNOPSIS. In this study the characteristics of the synthesis of DNA and RNA in the nuclei of Loxodes were investigated. Loxodes striatus is a primitive ciliate with 2 pairs of structurally differentiated diploid nuclei, the macro- and micronuclei. The macronuclei are differentiated morphologically into a clearly recognizable central core and an outer zone.To determine DNA and RNA synthesis, individual organisms were analyzed by autoradiography after incubating groups of cells with a 3H-labeled precursor ([3H]thymidine for DNA and [3H]uridine for RNA).The following observations were made: (A) All portions of macro- and micronuclei appeared to contain DNA as judged by the localizations of incorporated [3H]thymidine. (B) The macro- and micronuclei did not synthesize DNA at the same time; moreover, the duration of DNA synthesis in the former was much longer than of the latter nucleus. (C) Replication of DNA in the inner core and outer zone of the macronucleus occurred at separate times with little if any overlap. (D) All of the detectable [3H]uridine incorporation was found in the macronucleus and none in the micronucleus. Within the macro-nucleus the central core was more heavily labeled. (E) The quantitative differences in the label of the different components of the nuclear complex were investigated. (F) Contrary to the previously reported information our results suggest that DNA synthesis can occur in adult macronuclei.The possible explanation of these results is discussed in the context of the nuclear evolution of ciliates and of recent information on nuclear differentiation.

Notes: SYNOPSIS. Eimeria dispersa (turkey strain) and Eimeria gallopavonis sporozoites were inoculated into primary cultures of chicken kidney (CK) and turkey kidney (TK) cells. Eimeria dispersa sporozoites were more infective in either cell type than those of E. gallopavonis: at 4 hr, the percentage of infection was 67-98 for E. dispersa but only 23-56 for E. gallopavonis. E. dispersa also survived better in culture: at 2 days, losses of E. dispersa in both cell types were only 4-19%, whereas losses of E. gallopavonis were 35-47% in TK cells and 60–95% in CK cells. However, E. gallopavonis developed further than E. dispersa. Location and increase in numbers of intracellular stages at 4 days indicated that E. dispersa proceeded through 2 schizogonic generations before development stopped.

Notes: Book reviewed in this article:Cuatrecasas, P. & Greaves, M. F., eds. 1976, Receptors and Recognition, Vol. I, Series A.

Notes: SYNOPSIS. A mating type analysis was performed on 231 isolates of the cellular slime mold, Polysphondylium pallidum found in 61 samples collected in eastern North America between northern Florida and southern Canada. Seventy-eight percent of the isolates belonged to one of 2 mating types; 18% were incapable of mating with any partner; 3% were homothallic; and 1%, consisting of 2 isolates from a Florida sample, belonged to a separate breeding group. It is suggested that the majority of isolates represent a species capable of local genetic adaptation to a niche, the parameters of which undergo considerable variation over space and time.

Notes: Book reviewed in this article:Avakyan, A. A. 1976. Atlas Anatomii Prosteishikh, Patogen-nykh dlya Cheloveka i Zhivotnykh.

Notes: SYNOPSIS. Cell size, macromolecular composition, carbohydrate utilization patterns, and O2 concentrations were measured throughout the growth stages of Naegleria gruberi in agitated cultures in a complex medium. Biphasic logarithmic growth occurred during the initial 83 hr of growth and the mean generation time was 7.0 hr and 19 hr during initial and secondary log growth stages, respectively. The maximum yield was 5 × 10* amebaeJml. The pH rose rapidly (1 pH unit) during the secondary log growth phase (52-83 hr) and continued into the stationary growth phase (83-120 hr). Dry weight, total protein, carbohydrate, and RNA per ameba increased just before the secondary log growth phase. RNA increased 31% to 35% per ameba at the end of each phase of log growth. DNA increased ∼ 2-fold throughout the different growth phases. Average cell size increased 90% during biphasic log growth then decreased during stationary phase. O2 tension decreased from 100% to 18% of saturation during the biphasic growth phase, then increased during stationary growth to near 100% saturation. Glucose and total carbohydrate assays showed little utilization of those substrates throughout the growth stages. Naegleria gruberi presumably has a predominantly aerobic metabolism, also its metabolism may change during the different growth phases.

Notes: RESUME. L' étude ultrastructurale de la grégarine Gregarina blaberae a été entreprise après mise au point d'un protocole d'infestation expérimentale de larves vierges de Blattes, Blaberus craniifer. Les observations en microscopie électronique, effectuées en fonction du temps, ont permis de suivre le développement du sporozoïte, ainsi que la croissance et l' évolution du trophozoïte.La croissance est spectaculaire puisqu'en 18 jours elle entraîne la transformation du germe infectieux ou sporozoïte (L = 15 μm, φ=1 μm) en un céphalin—trophozoïte fixéà l' épithélium intestinal—de 250 μm de longueur pour un diamètre de 65 μm. L'organisation ultrastructurale du sporozoïte ne diffère pas de celle de la plupart des sporozoïtes des autres sporozoaires étudiés jusqu' à présent, le conoïde et les corps denses sont présents. La paroi est trimembranaire. toutefois le complexe membranaire interne présente quelques interruptions. Les premiers dictyosomes s' élaborent à partir de l'enveloppe nucléaire. La migration du noyau et des corps denses, puis la régression de toutes les formations caractéristiques du sporozoïte et l' établissement d'une zone corticale venant coiffer l' épimérite, ont lieu dans les 48 heures suivant l'infestation et marquent la transformation sporozoïte-céphalin.L' évolution du céphalin, se poursuit par la formation des ébauches des plis épicytaires qui s'effectue à partir du 3éme jour du développement à la base du deutomérite. Un système régulier de plis longitudinaux ou épicyte s' établit ainsi sur toute la partie extra-cellulaire de la grégarine. Dès les 4éme-5éme jours de développement, un réseau vacuolaire et un chondriome important se différencient dans l' épimérite, tandis qu'un septum de nature fibrillaire isole le protomérite du deutomérite. Le stade suivant—à partir du 6éme jour—est marqué par une ségrégation du matériel glucidique au niveau de ces 2 segments.Le modèle étudié permet de préciser le rôle de l' épimérite dansla nutrition du parasite, l' évolution du chondriome et des membranes corticales au cours de la phase de croissance végétative des grégarines polycystidées.

Notes: SYNOPSIS. Stomatogenesis was studied in the heterotrich ciliate Blepharisma japonicum stained with protargol. During binary fission not only is a new oral apparatus made for the posterior daughter, but the already existing oral apparatus of the parent cell is reorganized, i.e. partially disassembled and then subsequently reassembled to provide a functional feeding apparatus for the anterior daughter cell. These morphogenetic events, requiring 21/2 to 3 hr, are complete by the time the anterior and posterior daughters separate.In preparation for division, an oral anlage is formed by the rapid proliferation of kinetosomes along 4–5 stomatogenic kinetics directly subtending the cytostome. This field of randomly oriented kinetosomes ultimately gives rise to the feeding apparatus of the posterior daughter cell. Early in division, the oral anlage separates into 2 longitudinal fields of kinetosomes: one is destined to give rise to the undulating membrane and the other forms the adoral zone of membranelles. Shortly after the anlage is established posterior to the cytostome, reorganization of the existing functional mouth is initiated. The morphologic changes associated with this dedifferentiation-redifferentiation sequence lead to the formation of an oral apparatus for the anterior daughter and cannot be distinguished from those characteristically seen during physiologic reorganization.

Notes: SYNOPSIS. The effects of age and sex of the cat on oocyst shedding, multiplication of Toxoplasma gondii in tissues of cats, and acquisition of immunity were investigated after oral inoculation of cats with Toxoplasma cysts. Twenty-five cats varying in age from 1 week to 39 months were killed 7-97 days after inoculation with T. gondii. Homogenates of brain, heart, mesenteric lymph nodes, retina, and blood from these cats were inoculated into mice to test for Toxoplasma infectivity. Toxoplasma was isolated more frequently and in higher titers in mice receiving inocula from cats of the youngest age group (1 week old). Toxoplasma gondii was isolated from tissues of only 2 of 21 cats older than 2 months (at the time of inoculation), although all of the animals shed oocysts within 1 week after ingesting the parasites.The number of oocysts shed varied among littermates of the same sex and between sexes. Generally, cats younger than 12 months shed more oocysts than older cats. The number of oocysts shed by older cats varied considerably; males generally shed more oocysts than the females. However, the numbers of cats examined were too small for statistical comparison. Nevertheless, the observations suggest that cats older than 12 months should not be used in experiments where numbers of oocysts shed is critical.

Notes: SYNOPSIS. Changes in the metabolism of Crithidia fasciculata ATCC 11745 when grown in the presence of ethidium bromide were studied. Ethidium bromide-grown cells had decreased respiratory activity as measured by oxygen consumption. More than 50% of the organisms cultivated in a defined medium containing 1.0 mg/liter of ethidium bromide became dyskine-toplastic and had decreased activities of particulate succinate and NADH-linked dehydrogenases as well as of soluble isocitrate dehydrogenase. These cells also had increased activities of particulate α-glycerophosphate dehydrogenase, soluble α-glycerophosphate dehydrogenase, malic enzyme, hexokinase, and malate dehydrogenase. Ethidium bromide-grown cells had a lower level of ATP and contained less DNA than cells grown in its absence.

Notes: SYNOPSIS. Phenol is the major organic constituent of coal-conversion scrub water and is therefore a potential environmental contaminant. After Tetrahymena pyriformis strain GL-C, syngen 1 was exposed to phenol, its behavior, cytology, respiration, and growth rates were examined. Concentrations ≥ 75 mg/liter alter cell motility, shape, and contractile vacuole activity. O2 uptake was abruptly reduced within 3 min of exposure to phenol in concentrations as low as 10 mg/liter. Concomitantly there was an increase in the electron density of the mitochondrial matrix. Recovery to normal rates of O2 consumption was paralleled by a return to normal matrix density. Alterations of mucocysts, pellicle, and glycogen were also observed. The length of lag phase growth curves increased generally in proportion to concentration of toxicant. Phenol, however, did not affect the rate of cell multiplication during the exponential growth phase. The potential use of this system to examine the effects of other possible organic pollutants is discussed.

Notes: SYNOPSIS. Sporulated oocysts of Eimeria nieschulzi Dieben, a rat coccidium, were exposed for 1 hr to Cobalt-60 γ-radiation (15, 30. or 60 k-rads), to heat (35, 40, or 45 C). or to both concurrently (15, 30, or 60 k-rads at 35 C) to compare the excystation capabilities of treated vs nontreated parasites. Intact, treated oocysts appeared structurally unaltered when viewed with the light microscope. Excystation of sporozoites occurred in all treated groups when their sporocysts were exposed to a trypsin-sodium taurocholate (TST) fluid, but after 150 min in TST the excystation rate was significantly lower than in non-treated sporocysts. Sporozoites which excysted from treated sporocysts were abnormal both in the excystation process and in their form and movement once outside the sporocyst.

Notes: SYNOPSIS. Mitochondria were isolated from Euglena gracilis strain Z by pressure-breakage of the cells and sucrose-cushion centrifugation. Multiple peaks (2-4) were observed in the rate of phosphorylation with Mg-ADP-phosphate concentration curves. The phosphorylative and oxidative activities were highest with NADH as the substrate, moderate with succinate, and lowest with glutamate. Inhibition of phosphorylation with 2,4-dinitrophenol and carbonyl cyanide, m-chlorophenylhydrazone gave sigmoidal concentration curves, with the extent of inhibition by DNP depending on the substrate used. Inhibition of phosphorylation by valinomycin, atractyloside, or carboxyatractyloside was only ∼ 60%. Oligomycin inhibited phosphorylation in 2 phases at low and high concentrations; it inhibited Mg-ATPase in a sigmoidal fashion. Both phosphorylation and oxidation had discontinuities in Arrhenius plots at 34 C and 18 C.The relative Mg2+-dependent nucleoside triphosphatase activity was: 1 for ATP and GTP, 0.6 for ITP, 0.15 for CTP and and UTP; with Ca2+ in place of Mg2+ this activity was 0.35. Both DNP and CCCP stimulated the Mg-ATPase 50-200%. The optimal pH for the stimulation was ∼ 7 regardless of the uncoupler used, and ∼ 8 without the uncouplers.The few differences observed between mitochondria from Euglena and those from other sources are probably due to the fragmentation of the reticular mitochondrial structure during isolation and not to unique characteristics of these mitochondria.

Notes: Book reviewed in this article:Jennings, D. H., Lee, D. L., eds. 1975. Symbiosis (Symposia of the Society for Experimental Biology Number XXIX).

Notes: Book reviewed in this article:Stanier, R. Y., Adelberg, E. A. & Ingraham, J. L. 1975. The Microbial World, 4th ed.

Notes: SYNOPSIS. Discotricha papillifera Tuffrau, a marine interstitial ciliate, is redescribed with the aid of light, scanning, and transmission electron microscopy from cells collected at a New Hampshire beach. Presence of primitive membranelles as well an an advanced stomatogenesis is demonstrated. The ultrastructure, including a unique membrane-bounded septate structure, is described. The cell is tentatively placed in the nassulid suborder Microthoracina, but affinities with other groups are discussed.

Notes: Book reviewed in this article:Noble, E. R., Noble, G. A. 1976. Parasitology. The Biology of Animal Parasites. 4th Ed.

Notes: RESUME. L' étude détaillée du cortex et des organelles buccaux adoraux d' Espejoia montre que ce Cilié possède une organisation ultrastructurale comparable à celle des Tétrahyméniens. Tout en restant conforme au plan général d'organisation de ces derniers, des variations spécifiques décelées tant au niveau du cortex d'une part, que des membranelles, d'autre part, font ressortir des affinités trés marquées pour le genre Glaucoma et autres Ciliés voisins. En conséquence, en nous appuyant en outre sur les données récentes de la morphogenèse, nous confirmons la position d' E. mucicola parmi les Tetrahymenina, dans la famille des Glaucomidae.

Notes: SYNOPSIS. Budding and metamorphosis in the suctorian ciliate, Discophrya collini, have been investigated by scanning electron microscopy. The adult body form, tentacles, stalk, and attachment disk are described. A field of depressions or small pits was observed in the pellicle of adult suctorians in the early stages of bud formation. These pits deepen and coalesce until one large pore, the birth pore, remains. Cilia protrude through the pore, and as eversion of the bud proceeds the meridional arrangement of the larval ciliation is evident. After eversion is completed, a pronounced division furrow is found between the adult and soon-to-be-released swarmer. The stalk-forming region is seen on swarmers. Metamorphosing swarmers produce tentacles upon settling before any indication of ciliary resorption. Resorption of cilia and change in body form occur progressively with the production of the attachment disk and stalk.

Notes: Book reviewed in this article:Cohen, S., & Sadun, E. H., eds. 1976. Immunology of Parasitic Infections.

Notes: Book reviewed in this article:Herman, C. M., Greiner, E. C., Bennett, G. F. and Laird, M. 1976. Bibliography of the Avian Blood-Inhabiting Protozoa.

Notes: SYNOPSIS. Marine, sediment-dwelling ciliates were examined for cytochrome oxidase activity by a cytochemical method and for fine structural details. Species of Plagiopylidae (Trichostomatida), i.e. Plagiopyla frontata, Sonderia vorax and Sonderia sp., and of Heterotrichida, i.e., Parablepharisma pellitum, Parablepharisma sp., Metopus contortus, Metopus vestitus and Caenomorpha capucina; previously considered to be obligate anaerobes because of their sulfide-containing habitat, do not have cytochrome oxidase activity or mitochondria with cristae or tubuli. The evolutionary origin and significance of anaerobic ciliates is discussed. Most of the anaerobic ciliates harbor a flora of ecto- and endosymbiotic bacteria as demonstrated by transmission and scanning electron micrographs. It is speculated that the bacteria may utilize the metabolic end products of the protozoa for growth and energy yielding processes. These associations are also compared with other, previously described cases of symbiosis involving prokaryotes and protozoa.

Notes: The paper is concerned with the concept, definition and measurement of a service. Although services are often dismissed as immaterial goods, they are not special kinds of goods and belong in a quite different logical category from goods. The search for appropriate units of quantity in which to measure services is not an idle metaphysical pursuit. Without quantity units there can be no prices, and most economic theory becomes irrelevant. Indeed, large parts of economic theory may be irrelevant to the analysis of services anyway, precisely because they are not goods which can be exchanged among economic units. Services are as important as goods in modern developed economies and they need to be identified and quantified properly if the measurement of economic growth and inflation is to have any meaning for the economy as a whole. The concept of a service is explained in some detail in the paper, and various ways in which services can be classified for purposes of economic analysis are elaborated. The distinction between private and public goods, or rather between private and collective services, is re-examined in the light of the general concept of a service proposed in the paper. Externalities are shown to be simply special kinds of services.

Notes: This article examines several hypotheses concerning the stochastic nature of year to year variations in individual incomes in light of newly available microdata on individual earnings. In particular, the models of Solow (1951), Champernowne (1953), and Rutherford (1955) are examined in some detail, and their predictions as to changes to be expected in the distribution of individual incomes are tested. The author concludes that the distributions arrived at using these models are not very similar either to each other or to the actual distribution of earnings. Thus, he believes that as an “explanation” of earnings dynamics stochastic process models are unsatisfactory. He further criticizes these models on the grounds that they foster a bias toward the belief in the inevitability, and perhaps desirability, of the current distribution of earnings.

Notes: This paper investigates the relation between schooling and earnings across and within occupations. Across occupations earnings are positively related to mean education. Within occupations the variance in schooling levels is generally substantial, but within two thirds of the occupations no relation between schooling and earnings is observed, while in the remaining third the pattern of sensitivity varies considerably. The sensitivity of earnings to education is greater for white males than white females and substantially greater for whites than blacks. When the white sample is divided into age cohorts, the degree of sensitivity of earnings to schooling is found to be greater for younger cohorts than older ones, except for the youngest cohort in 1970. In the conclusion, a structural interpretation of the distribution of earnings is proposed to account for the findings.

Notes: The historical background and present methodology used in compiling the U.K. official estimates of the stock of fixed capital are described. Mention is made of the possibility that with the development of commercial accounting direct estimates of capital stock may be derived from enterprise accounts at some future time. For the present, however, an indirect perpetual inventory approach is followed. Some of the deficiencies of the present estimates are discussed including the effects of possible biases in the life-length assumptions, price indices and the treatment of secondhand assets. Estimates of gross capital stock are given analysed by industry group of ownership and by type of asset.Some conceptual issues are discussed in relation to user requirements, including the distinction between the stock of capital and the flow of services from it.The authors conclude that little can be done to improve the perpetual inventory estimate of fixed capital in the U.K. without devoting more resources to the collection and analysis of new information, particularly on the service lives of fixed assets, the extent of leasing and the transfer of assets between industries.

Notes: This paper is concerned with the theoretical problems of devising indexes of quality change and with some of the practical problems of constructing such indexes from market data, relating these to the various attempts to construct such indexes in the past. The general conclusion is that, while quality is inherently ordinal, there are three different indexes which might be taken as “measures” of quality change. If changes are sufficiently small, the values of all three indexes will coincide and then, only, can we consider any one of them to be an unambiguous measure of the change.

Notes: This paper assesses the effects of including wealth and the variability of income on the incidence of poverty and the degree of income inequality in Israel. A special survey, which includes data on the wealth and income of a national sample of Israeli families in 1963–64 and 1964–65, allows us to go beyond measures based on current income alone.The first section reviews earlier studies of poverty in Israel. The next section looks at poverty and inequality in terms of current income, current wealth, and a combined measure of income and wealth. The combined measure is the Hansen-Weisbrod measure (HW), which equals income plus the annuity value of wealth, assuming all wealth is just consumed at the time of death. It is interesting that, in spite of the much higher wealth inequality than income inequality, the HW measure was slightly more equally distributed than income. This result occurred because the annuity component made up a low share of the total HW measure and the correlation between income and wealth was well under 1. Although overall inequality and poverty were similar for income and HW measures, the incidence of poverty by subgroup depended on the measure used.The final section presents a dynamic view of poverty and inequality. Year-to-year changes in poverty were substantial. Because of the use of a relative poverty concept and the rise in real incomes, the real income poverty line rose by 15 percent between 1963 and 1964. Still, of those in income poverty in 1963, 37 percent managed to escape poverty in 1964. The paper shows how the degree to which poverty was stable or transitory varied substantially by age and country of origin.

Notes: The main purpose of this paper is to discuss some of the measurement problems in connection with the perpetual inventory method applied for estimates of capital stock. In the Federal Republic of Germany, highly aggregated capital stock data by business sector are compiled by the Federal Statistical Office within its national accounts calculations, while more detailed capital stock estimates by industrial sectors are published by the German Institute of Economic Research (DIW) in Berlin. Because of various gaps in the statistical sources, the accuracy of the capital stock calculations is not yet entirely satisfactory. Aside from the problem of establishing long time series for gross fixed capital formation in constant prices for all sectors, it is difficult to obtain reliable data on the inter-sectoral transactions in secondhand capital goods. In addition, there are problems of determining price indices and service life distributions of the fixed assets in the various parts of the economy. This paper shows a way to arrive at a reasonably close approximation to the latter problem.

Notes: Recent attempts to measure value of household work and other non-market activities have been based on a simplistic interpretation of Opportunity Cost of Time Theory; this paper attempts to refine this and develop practical definitions from basic Utility Theory. First a distinction is made between economic and other activities, the former being the only ones subject to dollar-measurement; we recognize economic activities can occur outside the market and focus our analysis upon these latter. In the framework of Becker-Lancaster a Household-Production Function is posited which produces jointly such non-market economic activities-called indirect utility-and welfare or satisfaction- called utility. A criterion for identifying the indirect utility activities (Third-Person Criterion) is outlined, and related to time-use survey data.Finally, four practical estimation methods are outlined: simple opportunity cost of time; gross replacement cost; individual function replacement cost; and the full production function approach. This latter, which includes evaluation of capital contributions, is deemed theoretically most valid but for present purposes least practical because of lack of data on domestic capital stock. The paper concludes that there exists both a theoretical basis for valuing non-market activities, and the necessary data to apply the formulas developed.

Notes: Starting out from the observation that both imports and exports may be viewed as the difference between domestic consumption (use) and production, static standard theory of biases in consumption and production indices is brought to bear upon trade indices: Laspeyres tends to overrate when applied to imports and to underrate when applied to exports; for Paasche, the opposite holds true. Hence, terms of trade tend to be underrated (exaggerated) when based upon Laspeyres (Paasche) price indices. The problem of extending these conclusions to the case of changes in production frontiers and preference maps is discussed. When homotheticity is absent, correlation between price and quantity relatives may upset the simple conclusions. This is of special importance in the large-country situation. Dynamics further complicate the situation. A cobweb mechanism in exports may thus reverse the static results.

Notes: This article considers the major results of a study of relative wage structures in the LAFTA region. It first discusses the nature and methodology of the study, which was undertaken for ECIEL. Data on the size of labor income differences are introduced, and an attempt is made to determine the causes of such differences, and to relate them to various wage differentials. The main findings of the study are then summarized, with discussions of inter-country, intra-country, and occupational labor income differentials and their causes. Finally, the results of the study are updated to the end of 1970, and some conclusions are derived regarding the inter-temporal behavior of wages in LAFTA.

Notes: Some relationships between NNP and economic welfare are explored in the confines of a simple, static welfare maximization model. Various assumptions concerning both the measurement of NNP and the economic system underlying this model are dropped seriatem and the implications for the correspondence between NNP and economic welfare are examined.The following conclusions emerge. There are several classes of resource reorganization in which NNP and welfare move in the same direction, so that NNP can serve as an ordinal proxy for welfare. These include changes in taxes or competitive imperfections which result in product substitution and movements along the transformation function.With a general qualification, NNP-welfare correspondence is preserved for allocative changes which affect the real costs and prices of goods included in NNP or of non-included goods in inelastic demand; changes in involuntary unemployment; and changes in technological externalities affecting producers. There are other cases where changes in NNP and welfare are not positively correlated. Included here are changes in real costs of non-included goods for which demand is elastic and changes in technological externalities imposed on consumers.

Notes: The purpose of this paper is to describe the conceptual and statistical basis of the estimates of United States public and private spending for pollution abatement and control (PAC) prepared by the Bureau of Economic Analysis, U.S. Department of Commerce. The concepts and definitions were designed to ensure comparability with the national economic accounts since much of the analysis of the effects of environmental programs on the economy is conducted with the aid of the accounts. The work to date has been limited to pollution associated with harmful “foreign” substances and forms of energy discharged in the course of production, distribution and consumption. The conceptual base includes evaluation of benefits, but estimates completed thus far are limited to the cost of pollution abatement and control.Definitions are given for pollution, pollution abatement, direct pollution abatement cost, indirect pollution abatement cost and indirect benefits. A framework for the estimation and presentation of PAC expenditures is developed and the estimate of U.S. PAC expenditures for 1972 and 1973 is presented. A brief chronological summary of the BEA project is also provided.

Notes: This paper computes new indexes of output for refrigerators, using hedonic methods to adjust for quality change. The hedonic technique is applied in a new way (it is used to make quality adjustments to prices before they are used in the index), and the results are compared with those from methods used in previous hedonic investigations.There are three major findings. (1) Overall (1960–1972), our hedonic deflated output series rise more rapidly than conventional measures, because the price indexes used for deflation rise more slowly. (2) The output measures fluctuate more than do output measures produced by conventional methods, because adding hedonic quality adjustments to WPI indexes moves them up in some years and down in others, and the resulting adjustments to the output series were positively correlated with changes in output. (3) Applying methods used in previous studies produces larger adjustments to the published indexes, suggesting that some of the differences noted in previous studies between hedonic indexes and official published indexes are related to computational methods, not to quality adjustment.

Notes: The multiplier effects resulting from an isolated increase in the level of public consumption within different public branches are investigated and the policy implications are discussed. The article begins with a theorethical analysis which shows why and in which ways these multipliers can be expected to differ between public branches. Thereafter, an empirical investigation is given, based on simulations with an econometric model of the Swedish economy. In this model the public activities are divided into 13 different public branches. The effects of an increase in public consumption on employment, imports and private consumption are found to differ considerably depending on which branch of the public sector is expanded. Some implications for short run stabilization policy are discussed. The article ends with a special analysis of the implications for a medium term planning problem: the trade off between private and public consumption growth. This analysis throws new light on the old topic “private or public consumption”. In an economy with highly differentiated production in the public sector the trade-off is shown not to be unique. The sacrifice of private consumption growth corresponding to a given growth of public consumption expenditures will vary considerably according to the distribution of the public consumption growth within the different branches of the public sector.

Notes: The paper reports experience in constructing social accounting matrices (SAMs) for three national economies, viz. Iran, Sri Lanka and Swaziland. The SAMs focus particularly on the distribution of income through disaggregation of household sector income and outlay accounts consistent with more conventional disaggregation of production, factors, etc. The SAMs were conceived as an initial step towards understanding income distribution as an integral part of the development process and have been developed in parallel with work on planning models. Both the Iran and Sri Lanka SAMs were constructed within the context of the International Labour Office, World Employment Programme: that for Iran was intended as a contribution to the work of the Comprehensive Employment Strategy Mission to Iran under WEP auspices; while the Sri Lanka SAM was more specifically a research oriented study. The Swaziland study was financed by the Overseas Development Ministry, London as a research activity.Some learning-by-doing was involved in the sequence of SAMs and the problems encountered, solutions adopted and lessons learned provide the main substance of the paper.

Notes: Household budget data collected in 1966–1971 in eleven cities in six South American countries are used to define individual mean budget structures (means of budget shares across households). These structures are then compared by indexes of dissimilarity, calculated for the entire budget and also for major components: food, animal protein foods, nonfood, and housing and clothing. Differences among cities in real income account for much of the difference in the share of the consumer budget devoted to food, which in turn is a principal source of overall budget dissimilarity. Within the food and nonfood budgets separately, income is of somewhat less importance; prices and preferences become more significant. Budget structures tend for this reason to be similar for cities in the same country. The structure of nonfood spending also varies markedly between coastal and interior cities, largely because of differences in housing costs. The available price data account for dissimilarities which depend on the price of a single large category of spending, but they do not help explain structural differences involving many categories: prices seem more important for nonfood than for food expenditures. Regression analysis is used to weigh the importance of each variable contributing to dissimilarity.

Notes: This paper considers the need for a more integrated system of social and demographic statistics than SSDS and discusses the advantages of building it on the concept of life expectancy. The system would include a network of additive tables which would (as SNA does for economic variables) bring together leading social variables in a way that would permit the effects of exogenous changes to be quantified and compared. The author proposes as the base of such a system a table giving the expected duration of various life states (education, employment, retirement, etc.). This would be supplemented by a family of social co-efficients and fixed-weight index numbers that slot into it, allowing inter-temporal and international comparisons. The system would facilitate analysis of inequalities (regional, ethnic, etc.) and social change, and government planning of such change. It would also provide a framework for the development of national systems of social statistics.

Notes: The relevance of national accounts data to the broad development planning process which spans varying time horizons is considered. Undue emphasis on aggregated conventional macro-economic variables and recorded monetary values may have distorted the real vision and objectives of development. At the same time, other important and measurable problems like regional and distributive imbalances have often remained unquantified in traditional planning models. The UN “Supply-Disposition” table permits a summary description of the basic structure of an economy which can be easily extended within the context of the complete SNA to embrace significant social features without resort to complex inter-industry relationships. The table, however, loses few of the important dynamic economic properties of a full I–O system. It retains the means of checking the consistency of both overall policy objectives as well as basic data and it enables governments to ensure the necessary equilibrium between physical resource flows and financing capacity in formulating their development plans. The system's internal logic, combined with its potential for greater relevance and flexibility and capacity for fairly rapid and regular up-dating, makes it a most useful tool for practical planning purposes. Case studies of Zambia, Fiji and Oman are used to illustrate the fundamental concepts and underlying schematic framework of the system and its flexibility.

Notes: This paper collects and extends the available data on size distribution of income by country, and then uses these data to develop an hypothesis about the relation of stage and mode of development to the distribution of income. In particular, the author attributes the increase in income inequality which often occurs in the early stages of economic development to the uneven spread of capitalist modes of production, which leads to a dualism which separates the capitalist sector from the rest of the economy. The author goes on to discuss the role of this dualism in increasing the inequalities existing in the society. Finally, the author contrasts the income distributions found in socialist countries with those of capitalist ones, and concludes that it is not economic growth per se, but rather the capitalist mode of production, which creates income inequalities in developing countries.

Notes: In its first part, this note is a summary of the French version of the discussion paper submitted to the present IARIW Conference./〉 The second part is devoted to theoretical aspects of aggregation, as regards preference aggregation, and gives necessary and sufficient conditions which are useful for our purposes.

Notes: This paper is concerned with the definition and measurement of poverty in Malaysia. A poverty line is estimated after considering both the absolute and relative approaches to the definition. Various indices of poverty are discussed, ranging from the simple “incidence of poverty” measure to others which take account of the “poverty gap”. There is a derivation of a new index due to Sen, and alternative normalizations are suggested for it. Estimates of all these measures are presented for Malaysia. Finally, the simple “incidence of poverty” measure, which is decomposable, is adopted to construct a “profile” of the poor in Malaysia.

Notes: This paper is divided into two sections-the first section discusses the history and development of Canadian low income cut-offs developed by Statistics Canada and the second examines problems relating to the adequacy of one year's income and the treatment of wealth in the low income data.The first section summarizes the conceptual basis of the Statistics Canada low income cut-offs that were first introduced for an analysis of 1961 Census data; a description of the data sources for specifying the cut-offs and examining the low income population is presented; a recently incorporated revision is described; and uses and abuses of the Canadian low income cut-offs are described.The second section discusses two main issues. The first issue relates to the adequacy of one year's income as a poverty criterion. Between years there is a significant amount of movement in and out of low income status which varies by socio-demographic characteristics.The second issue relates to the effect of ignoring wealth in the derivation of the low income population.The two concerns are examined empirically with data from the Canadian Survey of Consumer Finances.

Notes: The accuracy of the two most common arrival time functions used in seismic velocity estimation is investigated. It is shown that the hyperbolic arrival time function is more accurate than the parabolic arrival time function for a horizontally layered elastic medium. An upper bound on the difference between the two arrival time functions is given.A maximum-likehood detector for estimating the arrival time of the signals is given. For the signal-in-noise model that is used the maximum-likelihood detector is equivalent to a least-squares detector which corresponds to using the signal energy as coherency measure. The semblance coefficient corresponds to a normalized least-squares detector. The semblance coefficient is very similar to a filter performance measure that is used in least-squares filter design.

Notes: The proposed system works as follows:〈list xml:id="l1" style="custom"〉1By a trial-and-error procedure using a graphic display terminal a geologically relevant layer sequence with parameters (ρj, dj) is adjusted to yield roughly the measured curve.2The resulting layer sequence is used as starting model for an iterative least squares procedure with singular value decomposition. Minimization of the sum of the squares of the logarithmic differences between measured and calculated values with respect to the logarithms of the resistivities and thicknesses as parameters linearizes the problem to a great extent, with two important implications:〈list xml:id="l2" style="custom"〉a) a considerable increase in speed (the number of iterations goes down), thus making it cheap to achieve the optimum solution;b) the confidence surfaces in parameter space are well approximated by the hyper-ellipsoids defined by the eigenvalues and eigenvectors of the normal equations.Since these are known from the singular value decomposition we do in fact know all possible solutions compatible with the measured curve and the geological concept.〈list xml:id="l3" style="custom"〉3It is possible to “freeze” any combination of parameters at predetermined values. Thus extra knowledge and/or hypotheses are easily incorporated and can be tested by rerunning step (2). The overall computing time for a practical case is of the order of 10 sec on a CDC 6400.

Notes: Ott and Meder's prediction error filter can be rederived so that it correctly handles input noise vectors which are of smaller dimension than the state vector. The poor performance obtained by Ott and Meder for their example can be explained by means of the error covariance matrix for the prediction error filter.

Notes: The contribution of electromagnetic phase comparison techniques to distance measuring is reviewed in an historical context. Special emphasis is accorded the new class of near infra-red electro-optic instruments suited to the measurement of distances under 2 km with an accuracy of a few millimetres. Principles of operation, sources of error, and practical applications are discussed.

Notes: A magnetotelluric digital equipment has been designed and built for operation in geophysical and applied geophysical research. The five components of the natural electromagnetic field can be digitized in the frequency range 1/1000 Hz (magnetic sensor's response limits) to some tens Hz.The magnetotelluric (MT) data are directly digitized in the field and stored in a cassette tape recorder.

Notes: An electromagnetic frequency sounding experiment with a rigid horizontal transmitter coil carrying a stabilized oscillating current was carried out in South Tunesia.The field data were interpreted in terms of the mutual impedance ratio in the horizontal coils system. Where the measurements were sufficiently accurate they generally could be interpreted to a high degree of fit. It is concluded that a vehicle-mounted electromagnetic frequency sounding system is suitable for a fast survey.

Notes: The application of approximate rules, whereby apparent resistivity space sections for two dimensional structures can be composited from spaces derived for elementary features is extended to a complex example drawn from a field survey over a fluorite mineral vein.A quantitative solution for the observed resistivity space is presented and the computational sequence involved in matching the observed space is given in detail.The interpreted results are examined in relation to the known geology, supplemented by the results of excavation, and to model tests conducted using a tank analogue.The example also illustrates how successive compositions can be employed in estimating the form of resistivity space in a relatively complex situation.

Notes: The sampling theorem in two dimensions univocally defines a surface, provided that its values are known at points disposed on a regular lattice. If the data are irregularly spaced, the usual procedure is first to interpolate the surface on a regular grid and then to contour the interpolated data: however, the resulting surface will not necessarily assume the prescribed values on the irregular grid.One way to obtain this result is to introduce a transformation of the coordinates such that all the original data points are transferred into part of the nodes of a regular grid. The surface is then interpolated in the points correspondent to the other crosspoints of the regular grid; the contour lines are determined in the transformed plane and then, using the inverse coordinate transformation, are transferred back to the original plane where they will certainly be congruent with the original data points.Nonetheless, the resulting surface is very sensitive to the interpolation method used: two algorithms for that are analyzed. The first (harmonization) corresponds to the determination of the potential of an electrical field whose contour conditions are those defined by the data points. The second method consists in two dimensional statistical estimation (krigeing); in particular, the effects of different choices for the data auto-covariance function are discussed.The solutions are compared and some practical results are shown.

Notes: Optimum stacking filters based on estimates of trace signal-to-uncorrelated noise ratios are assessed and compared in performance with conventional straight stacking. It is shown that for the trace durations and signal bandwidths normally encountered in seismic reflection data the errors in estimating signal/noise ratios largely counteract the theoretical advantages of the optimum filter. The more specific the filter (e.g. the more frequency components included in its design) the more this is true. Even for a simple weighted stack independent of frequency, the performance is likely to be better than a straight (equal weights) stack only for relatively high signal/noise ratios, when the performance is not critical anyway.

Notes: Electromagnetic coupling in grounded electrical prospecting systems has been studied over four decades. Recently, advanced digital electronic systems have been developed which permit both magnitude and phase measurements over four frequency decades (10−2— 102 Hz). This development has stimulated theoretical studies demonstrating behavior of EM coupling for the more commonly-used electrical prospecting arrays a wide frequency range. A comparison is made between field and theoretical results which demonstrates the validity of the fundamental assumptions involved. Additionally electromagnetic coupling is used successfully as a deep-sounding technique in a highly-conductive sedimentary basin environment.

Notes: A polygonal ray path connects the seismic source and detector positions when the intervening medium consists solely of constant velocity layers with plane interfaces which may have arbitrary orientation. The coordinates of the ray vertices satisfy a system of coupled equations resulting from the requirement that Fermat's principle be satisfied along the ray path. Solving the system of equations is equivalent to tracing the ray numerically. A notable feature of this approach is that a ray which is critically refracted over a segment of its path requires no special handling.

Notes: A satisfactory attenuation of the multiples in marine seismic may be obtained by the application of the principle of “Antiaveraging”.This principle in a first step consists in getting the model of the organized noise, which one tries to eliminate by using an averaging method, and in a second step to subtract that model from the initial information.Obviously the elimination of the model should not simultaneously cause the elimination of useful signals.The model may be obtained if the considered organized noise keeps a constant shape or if its time-space deformation is known. Besides one has to assume the time-distance curve of the organized noise can be determined. Thus noise arrivals may be detected on the records.The “antiaveraging” is very often efficient when organized noises are stronger than signals or when a signal, once identified, exploited and then considered as an organized noise, can be attenuated in order to make the detection of the other signals easier.

Notes: Two experiments in which early-weaned lambs (4–7 and 5–9 weeks of age) continuously grazed a perennial ryegrass-white clover sward are described. In both experiments groups of lambs were offered a proprietary concentrate ad libitum, 2/3 or 1/3 of ad libitum allowance, or no concentrate. Mean daily gains over 56 days in Experiment 1 increased from 88 g without concentrate to 275 g with ad libitum concentrate allowance; the range in daily gains over 71 days in Experiment 2 was 201 g to 253 g respectively. In both experiments mean faecal OM output from herbage decreased as concentrate OM intake increased.

Notes: Four groups of ewes grazed swards of red clover (Trifolium pratense cv. Hungaropoly) for 28-day periods ending 28, 14 or 0 (two groups) days before mating. One of the groups on red clover for the period immediately before mating continued on red clover during mating. At all other times before mating and for 7–8 weeks after mating commenced these ewes were grazed on a predominantly perennial ryegrass-white clover sward. A fifth (control) group was on the ryegrass sward throughout. There was no apparent adverse effect of red clover on ovulation rate, conception rate or embryo mortality.

Notes: A non-protein nitrogen additive containing ammonia, molasses and minerals was applied to precision-chopped forage maize to raise the crude protein content of the ensiled crop from approximately 8% to 10, 14 or 16%.The dry matter content, total nitrogen, water-insoluble nitrogen, and water-soluble nitrogen concentrations were measured at ensiling and 2 and 8 weeks later. The pH and lactic, acetic, propionic and butyric acid contents of the resultant silage were determined 2 and 8 weeks after ensiling.The levels of crude protein achieved were 10.8, 11.5 and 14.2%, which are equivalent to recoveries in the silages of 108, 82 and 89% of the applied nitrogen. After 8 weeks the water-insoluble nitrogen content of the treated silages had increased while the water-soluble nitrogen content had decreased. The increase in water-insoluble nitrogen may have been due to either decreased proteolysis or increased levels of microbial protein.There was a significant increase of 0.6 units in the pH of the silage when comparing the control to the highest rate of additive application. The additive increased the levels of lactic and acetic acid in the maize silage.

Notes: Methods of predicting the in vivo dry matter digestibility (DMD) of heather were examined in studies on ten samples of heather which had been fed to sheep in standard digestibility trials. DMD was predicted with similar accuracy from estimates of in vitro dry matter digestibility (in vitro DMD) and from the concentration of cell-wall constituents. In vitro DMD was found to be between 10 and 18 percentage units lower than DMD. Freeze drying the samples was the only modification to the technique which both increased in vitro DMD and the accuracy of the prediction of DMD. Other modifications attempted were the use of different liquor sources, changes in first-stage incubation time and dilution rate, and nitrogen supplementation of the inocula.The concentration of nitrogen or undigested dietary nitrogen in the faeces could not be used to predict the digestibility of heather with precision. It was concluded that the DMD of a heather diet could be satisfactorily predicted from the in vitro DMD of samples collected from sheep fistulated at the oesophagus.

Notes: The initial effect on the underlying sward of spraying bracken with 4.5 kg ha−1 a.i. asulam or 2.0 kg ha−1 a.i. glyphosate was to cause some damage which was greater if glyphosate was used rather than asulam or if treatment was carried out in August rather than in July. Agrostis species were especially susceptible while Festuca species were resistant. The recolonization of areas of bare ground after spraying was primarily by Holcus moliis, Anthoxanthum odoratum, Galium hercynicum and Potentilla erecta, but the population of the latter two species decreased as Agrostis became reestablished. If Digitalis purpurea, Urtica dioica or Cirsium arvense were present originally, heavy infestations developed following the use of asulam, with a smaller increase after glyphosate spraying. In all cases, by the end of three years after treatment, grasses occupied a greater area of the sward in treated than in control plots.

Notes: Three grass silages made in early June from S23 perennial ryegrass were compared in a 16-week feeding experiment with twelve Ayrshire cows. The silages were made from uniform herbage which received either formic acid (‘Add-F’) at the rate of 201 t−1, or a formalin-sulphuric acid mixture (‘Syiade’) at rates of 2.0 and 4.4 1 t−1. The silages were offered ad libitum either alone or supplemented with a cube containing 38% CP in the DM at the rate of 1.4 kg per 10 kg milk. The daily intakes of silage DM were not significantly different on the three silage treatments, and averaged 10.7, 11.0 and 11.0 kg per cow on the formic acid and the 2.0 and 44 1 t−1 formalin-acid treatments respectively. The mean daily yields of milk were 15.1, 13.3 and 13.7 kg per cow in the unsupplemented treatments, and 18.2, 18.1 and 18.0 kg per cow in the supplemented treatments on the formic acid and the 2.0 and 44 1 t−1 formalin-acid treatments respectively.On the basis of total animal production expressed in terms of metabolizable energy requirements, it was concluded that the differences between the three silages were small.

Notes: An experiment is described in which the amount of nitrogen fixed by the white clover component of a surface-sown hill sward was determined using small quantities of 15N-labelled ammonium sulphate. Between 11 July and 22 August 1974 25 kg ha−1 N was fixed. No evidence of a transfer of N from clover to the associated perennial ryegrass was detectable over this period although the N content of the grass growing with the clover was higher. The relative advantages of the isotope technique and the acetylene reduction assay are discussed.

Notes: Perennial ryegrass cv. S23 was preserved by fermentation (C), or with the addition of 8.7 1 formalin (35% w/w formaldehyde) per t fresh herbage (F) or of 9.0 1 equal mixture (by vol.) of formalin and formic acid (85% w/w solution) per t fresh herbage (FF). These three silages comprised the treatments in a three-period, crossover design in which urea (u) was given at the rate of 20 g per kg dietary DM to half the animals. Twelve calves were allocated to the treatment sequences when they were approximately 12 weeks of age from within groups which had previously received diets with or without urea.Calves ate significantly (P〈 0.001) less of silages F or FF than of silage C when each was offered alone, but when urea was given, intakes of silages F and FF were significantly (P 〈 0.001) increased such that the intakes of all three silages with urea were similar (23.6, 19.6, 19.3, 24.2, 24.2, 24.7 ± 0.51 g DM per kg LW for C, F, FF, Cu, Fu and FFu, respectively). Significantly (P〈0.01) more of the DM in silage C was digested than in F or FF and the addition of urea significantly (P〈0.05) increased the digestibility of DM from silage FF only (73.8, 71.3, 69.8, 74.6, 70.7, 72.5 ± 0.72% for C, F, FF, Cu, Fu and FFu, respectively). When the silages were given alone, calves spent longer eating and ruminating per kg DM ingested with F or FF than with C. The time spent on F and FF was significantly (P〈0.01) reduced by the addition of urea (303, 388, 411, 297, 299, 290 ± 18.9 min per kg DM ingested for C, F, FF, Cu and Fu and FFu, respectively).The results presented suggest that urea partially alleviated the reduction in voluntary intake by calves given herbage preserved using formalin, but the mode of action was not clear.

Notes: The intake of maize silage by self-fed heifers was measured where access to the silage was limited either by reducing the width of the feed face or by restricting the time allowed for feeding. In the first experiment twenty heifers were allowed 0.4 or 0.2 m feed face per head for 7 h daily. In the second experiment fourteen heifers were allowed 0.5 m feed face per head for 5 or 3 h daily. Intake was measured either by estimating faecal output by the chromic oxide technique and then using the in vitro estimate of silage digestibility to calculate individual intakes, or by using the results of eight individually fed heifers to provide a direct relationship between the chromic oxide concentration of the faeces and total intake, and using this to predict the intake of the self-fed heifers from the concentration of chromic oxide in their faeces. The latter method was found to be the most satisfactory because it took into account the effect of level of feeding on the digestibility of maize silage. Restriction of access to the silage by limiting feed face width (Experiment 1) and time (Experiment 2) significantly reduced intakes by 4 and 7% respectively. In both experiments feeding time was significantly reduced by restriction, but this was partially compensated for by a significant increase in rate of eating.

Notes: In a small drainage basin in the Peak District rates of soil erosion were measured between October 1966 and September 1968. The vegetated margins of ground denuded of vegetation (scars) were retreating by 9.3 mm per annum and rills and sheet wash removed annually from these scars up to 34 t ha−1 soil. Erosion was taking place primarily within Agrostis-Festuca swards and also in heather moor, but not on peat-covered slopes under cotton grass (Eriophorum vaginatum) moor. The Agrostis-Festuca sward supported a higher sheep population than did the other vegetation types. In May 1974 most scars had been colonized by vegetation; this was related to a marked decrease in sheep numbers in 1969 and not to climatic factors.

Notes: An experiment repeated in 3 consecutive years in which 0, 200, 400 and 600 kg ha−1 fertilizer N was applied annually is described. Cattle on all treatments were offered the same constant daily amount of 2.0 kg herbage DM per 100 kg liveweight above a 3.4 cm height of defoliation. Digestible OM intakes and daily rates of gain were in general not significantly different between treatments. Area required to support these intakes and gains however differed significantly between treatments (P 〈 0.001) and resulted in high outputs of liveweight gain per hectare on all treatments when compared with other published studies. These outputs together with other actual and theoretical outputs were used to predict optimum fertilizer N applications for grazing beef cattle and the predictions discussed in relation to commercial practice.

Notes: A comparison was made of some factors affecting digestibility in sheep and cattle. In one experiment four castrated male sheep and four non-lactating cows were given diets of hay and of hay and concentrates, and in another experiment similar groups of animals were offered diets consisting mainly of hay or hay and lucerne cobs. In both experiments there was good agreement in digestibility between the sheep and cows. With diets which did not stimulate maximum rumination, sheep tended to ruminate for a longer time per day than cows. At high feed intakes rumination times were similar in sheep and cows. Times spent eating, ruminating or chewing per unit of feed DM were 6 to 19 times longer in the sheep than in the cows. Retention times of stained hay in the gut tended to be slightly shorter in sheep than cows and those of stained barley husk and of processed lucerne were similar in the sheep and cows. The median size of faecal particles was 1.4 to 1.9 times greater in cattle than sheep. The similarities and differences between sheep and cattle in the factors affecting digestibility are discussed.

Notes: Grass silage made in late May from S24 perennial ryegrass was offered to twelve Ayrshire cows in a 16-week feeding experiment. The silage had a DM content of 25.3%, a pH of 3.91, and contained 16.8% CP and 68.4% digestible organic matter in the DM. The silage was fed ad libitum and was the sole feed in the control treatment. In the other three treatments the silage was supplemented with a cube offered at rates of 0.8, 1.4 and 2.0 kg per 10 kg milk. The cube contained 82.2% groundnut, plus molasses and minerals, and had 37.9% CP in the DM. The daily intake of silage DM was 11.4 kg per cow on average over the four treatments which did not differ significantly. The mean daily milk yields were 14.8 kg per cow in the control treatment, and 16.5, 18.2 and 18.4 kg in the 0.8, 1.4 and 2.0 kg supplement treatments respectively. The SNF, CP and lactose contents of the milk were Wghest on the 1.4 kg supplement treatment. It is concluded that with a high digestibility silage, there is little evidence to support the feeding of more than 1.4 kg of high-protein cubes per 10 kg milk in the declining phase of lactation.

Notes: The interpretation of total field anomalies becomes somewhat complicated, especially when an arbitrarily magnetized spherical ore mass happens to be the causative body. Even though some attempts have been made to analyze total field anomaly maps, they are often too complicated and their underlying assumptions in respect of permanent and induced components of magnetism are far from realistic. In this note, an attempt has been made to show that vertical magnetic anomalies are capable of yielding interpretation with ease and precision as far as magnetized spheres are concerned. An empirical method has been outlined for computing the magnetization inclination in the plane of the profile using the measured distances between principal maximum, principal minimum, and zero anomaly positions on a magnetic anomaly profile.

Notes: Pseudo velocity logs can be obtained by seismogram inversion, using true amplitude processing and detailed investigation of move-out velocities. The precision of the results depends on the quality of the seismic data and on the possibility of deconvolving without increasing the noise. An investigation is made of the deformation of pseudo logs due to seismic signal variations and to imperfections of deconvolution.Both marine and land examples are shown, in some cases with adjustment on well logs. When the dips are large, time sections must be migrated and pseudo velocity logs must be computed from migrated sections. Comparison of sonic logs with pseudo velocity logs obtained in the same area is usually good enough to obtain information on lithological parameter variations by adjustment of pseudo velocity logs on sonic logs. Even when no well is available, pseudo velocity logs can give some indications on the nature of sediments between seismic horizons.