May 15, 1896,] 



SCIENGE. 



749 



atmosphere of Mars must be regarded as unat- 

 tainable. With reference to oxygen, its presence 

 might possibly be detected- if present to the 

 amount of a quarter that in the earth's atmo- 

 sphere. 



In an article on A New Form of Kefraetom- 

 eter, Mr. C. Pulfrich describes one with a 

 scope of application including almost all quan- 

 titative investigations on refraction and dis- 

 persions at varying temperatures. Its essential 

 features consist of a 90° prism, one face of which, 

 turned upward and made horizontal, is brought 

 in contact with the object to be investigated, 

 while through the vertical face is observed the 

 boundary line limiting the light which, after 

 passing through the object, enters the prism 

 under grazing incidence. 



The latest article in the series on the ' Modern 

 Spectroscope ' is by Professor Newall. It is a 

 description of the new Bruce spectroscope con- 

 stituted for the Cambridge observatory. The 

 instrument is unique in being designed solely 

 for photographing spectra of the fainter stars 

 and in having no provision made for visual mi- 

 crometric measurements. A single white-flint 

 prism is used, giving a spectrum of 20mm. in 

 length between H/3 and K, or, with a telephoto- 

 combination, a spectrum of about 44mm. 



Other articles are, 'Light Curves of Variable 

 Stars Determined Photometically,' by Edward 

 C. Pickering ; ' The Arc Spectra of Rhodium 

 Ruthenium and Palladium, ' by Henry A. Row- 

 land and Robert R. Tatnall. 



Among the minor contributions is found a con- 

 cise summary of the properties of the X-rays 

 and a comparison of them with those of light 

 and cathode rays ; and a recommendation that, 

 in place of mercury as a reiJecting surface for 

 sextant and other work, a dark cylinder oil be 

 used, such as may be procured of any locomotive 

 •engineer. It is freer from vibration, cheaper, 

 lighter to carry, and easier to obtain in out-of- 

 the-way places. 



THE AMERICAN GEOLOGIST, MAY. 



The Genus Temnocyon and a New Species thereof 

 and the New Genus Hypotemnodon, from the John 

 Day Miocene of Oregon : By John Eyeeman. 

 The new species described is Temnocyon ferox, 

 of which a very complete and detailed descrip- 



tion is given. The new genus Hypotemnodon is 

 proposed for the reception of Cope's Temnocyon 

 coryphseus. 



Early Pleistocene Deposits of Northern Illinois : 

 By 0. H. Heeshey. The author discusses the 

 glacial geology of a part of northern Illinois, es- 

 p'ecially the Pecatonica valley, in which was 

 formed a glacial lake named Lake Pecatonica. 



On a Supposed Discovery of the Antennee of Triho- 

 lit.es by Linnseus in 1759 : By C. E. Beechee. 

 In the Geological Magazine for March, Tornquist 

 calls attention to a discovery, by Linnseus, of the 

 antennse of Parabolina spinulosa, which has ap- 

 parently been overlooked by later workers. 

 Dr. Beecher not only shows that this discovery 

 has not only been overlooked, but also that 

 what Linnaeus considered as autennse are not 

 antennae at all. 



The Deposition of Gold in South Africa : By S. 

 CzYSZKOWSKi. (Translated by H. V. Win- 

 CHELL.) The theories advanced by de Launay, 

 Jules Garnier and others to explain the origin 

 of the auriferous beds of South Africa are not 

 in all respects acceptable. Instead of the con- 

 temporaneous deposition of gold and mechanical 

 sediments of conglomeratic nature it is held by 

 M. Czyszkowski that the gold was introduced 

 by mineral waters circulating through the po- 

 rous strata subsequent to their consolidation, and 

 as an accompaniment of a period of general 

 earth movements and eruptive phenomena. The 

 auriferous strata are believed to occupy syn- 

 clinal basins in which the gold ores have been 

 developed in favorable situations. Summarized 

 descriptions of the geology of South Africa are 

 given, and several comparisons are made be- 

 tween these ore deposits and those of Spain. 

 The introduction of the gold is believed to have 

 been of Carboniferous age, and prior to the for- 

 mation of the Cape diamonds. From a more 

 detailed discussion of the geological structure of 

 the several Transvaal districts it is inferred, on 

 the one hand, that the ore deposits may be far 

 from inexhaustible ; while, on the other hand, 

 it is shown that there are many more geological 

 conditions and other horizons which appear to 

 be favorable for the concentration of gold ores, 

 and where explorations may be conducted with 

 profit. 

 Minerals and the Bontgen Rays : By W. G. Mil" 



