7 5 6 General Notes. [September, 



rasaurits and Atlantosaurus ; H. G. Seeley noticed Neusticosaung, 

 pusillus (Simosaunis pit sill us Fraas) showing that the structure of 

 its palate is generically different from that of any other plesiosaur; 

 A. VV. Waters gave a list of sixty-six chilostomatous Bryozoa 

 from Mount Gambier, South Australia, including twenty-eight 

 species now living, and fifteen not before described ; G. W. 

 Shrubsole described a new PhyUoportts from the Permian lime- 

 stones ; and Professor J. D. Dana made a communication upon 

 the geologic age of the Taconic rocks, maintaining their Silu- 

 rian age. 



MINERALOGY. 1 



The Manufacture of artificial Diamonds.— Since the now 

 famous experiment of Mr. Hannay in the manufacture of artifi- 

 cial diamonds, the subject has attracted great attention, and has 

 led to a number of experiments in the same direction:. 



Dr. R. S. Marsden has recently succeeded in producing minute 

 diamonds by a simple process depending upon the solubility of 

 carbon in fused metals, and its subsequent crystallization upon 



In a graphite crucible, lined within with a paste of gum and 

 charcoal, layers of powdered charcoal (prepared by calcining 

 sugar) are laid alternately with small lumps of pure silver, care 

 being taken to keep the silver always surrounded by the charcoal. 

 The closed crucible is then heated for ten hours at the tempera- 

 ture of melted steel, and then buried in hot sand so as to cool 

 very gradually. 



On opening the crucible the silver is found in a single lump 

 near the bottom, and shows a crystalline structure. The lump is 

 now dissolved in nitric acid, when the dissolved carbon remains 

 as a grayish-black powder of a bright graphitic luster. 



When examined under the microscope, this powder is seen to 

 consist of three different substances: (i) graphite, forming the 

 larger proportion; (2) an amorphous brown substance in flocks, 

 being either amorphous carbon or a carbide of silver ; (3) a num- 

 ber of small black octahedral crystals with curved edges. These 

 last are unattached by hydrofluoric acid or by any acids or al- 

 kalies, are hard enough to scratch quartz, and burn in a stream 

 of oxygen gas. These, therefore, appear 

 and it is probably merely 

 can be produced of sufficient size to be of value. 



Pyrites as a source of Sulphuric acid.— The use of pyrites 

 as a source of sulphuric acid has long been known, but it is only 

 within a few months that American pyrites has been used tor that 

 purpose. The distance of deposits of pyrites in this coU "^ 

 from manufacturing centers has been the chief drawback. iJ 

 1 Edited by Professor H. Carvill Lewis, Academy of Natural Sciences, 1*8* 



