ISSN:
1476-4687
Quelle:
Nature Archives 1869 - 2009
Thema:
Biologie
,
Chemie und Pharmazie
,
Medizin
,
Allgemeine Naturwissenschaft
,
Physik
Notizen:
[Auszug] In each pebble, a hole in. deep and 1/8 in. diameter was made. It was found that local flint from the beach was very difficult to drill, and a compromise had to be made by using pebbles of Permian Sandstone, with a few flints only, and also a number of pebbles made of cement. The pebbles averaged ...
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1038/178257a0
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