January 2, 1896] 



NA TURE 



205 



confined volume of nitrogen to act on metallic lithium. The 

 absorption was slow, but was so complete that the characteristic 

 bands of the nitrogen spectrum entirely disappeared. M. Des- 

 landres compares the reaction to the slow absorption of oxygen 

 by phosphorus, and points out that as a reaction of nitrogen 

 this is unique. 



An interesting contribution, by M. Osmond, to the existing 

 knowledge on the molecular structure of hardened steel appears 

 in the Bulletin de la Soci^ti cC Encouragement for November. 

 He states that in highly carburised steels, containing more than 

 1*3 per cent, of carbon, quenched lat temperatures above looo°, 

 there are two constituents, A and B, which differ widely in 

 their properties. The constituent A is the ordinary, hard, 

 strongly magnetic substance of which hardened steel containing 

 I per cent, of carbon is almost exclusively composed. Its hard- 

 ness is greater than that of orthoclase. B, on the other hand, 

 is only about as hard as fluorspar, and, as far as can be judged 

 by a study of its properties while mixed with A, is non-magnetic. 

 M. Osmond, however, has been hitherto unable to prepare B 

 free from A, although by quenching steel containing I '6 per 

 cent, of carbon at a temperature of from 1000° to 1100° in ice- 

 cold water, he has obtained a mixture of A and B in about 

 equal proportions. This mixture is comparatively very feebly 

 magnetic. The constituents both contain carbon, and exist side 

 by side in separate polyhedra. The author concludes that B is 

 the allotropic form of iron (denoted 7), which is especially stable 

 above 860°, and is present to the exclusion of the other forms of 

 iron in steels containing 25 per cent, of nickel, or 12 to 13 per 

 cent, of manganese, these steels beirg non-magnetic. The haid 

 constituent A would then be the allotropic form y3. The research 

 will be hailed by the allotropists as affording most important 

 evidence in favour of their theory. 



A PAPER on the temperature variation of the thermal con. 

 ductivities of marble and slate is contributed to the American 

 fournal of Science by B. O. Peirce and R. W. Willson. The 

 net result of their investigation is that such a temperature 

 variation does not exist ; in other words, that marble and slate 

 conduct heat equally well at all temperatures. This result is of 

 some importance to the physics of the earth's crust, and the 

 manner in which it was arrived at displays some ingenuity. 

 Two faces of a slab of marble or slate were kept at different 

 temperatures, and the fall of temperature between one surface 

 and the other was determined by means of thermopiles. Now 

 it is notoriously difficult to determine the temperature accurately 

 at a certain point, and borings lead to errors in estimated depth. 

 So the expedient was adopted of slicing the slab into a series of 

 layers pressed together, between every two of which a thermo- 

 couple was introduced. The interstices were only a few tenths 

 of a millimetre, and experiments with different intervals proved 

 that the error in the temperatures observed did not exceed one 

 or two degrees Centigrade. On plotting the temperatures and 

 distances, the temperature was found to have fallen uniformly 

 throughout the slab. If the conductivity had been higher at 

 higher temperatures, the fall on the hot side would have been 

 more decided. The temperatures ranged from 350° C. to zero. 



Attention may be drawn to a translation, in handy form, of 

 Prof. Hering's well-known addresses on " Memory as a General 

 Function of Organised Matter," and on " The Specific Energies 

 of the Nervous System." The little volume is issued by the Open 

 Court Publishing Company of Chicago, as part of the Religion of 

 Science Library, at a price of 1 5 cents. 



A CONCISE account of the work of Priestley, Scheele, 

 Cavendish, and Lavoisier, in connection with " The Discovery 

 of Oxygen, and its Immediate Results," which appeared recently 

 in the Pharmaceutical fournal, has been reprinted and published 

 in the form of a pamphlet, obtainable at the office of our con- 

 jemporar}'. 



NO. 1366, VOL. 53] 



A "Museum Report," containing a descriptive list of the 

 donations to the Museum and Herbarium of the Pharmaceutical 

 Society during 1893-94, has been prepared by Mr. E. M. 

 Holmes, Curator of the Museum, and published by the Society. 

 The catalogue contains interesting notes concerning the more 

 important donations, and the complete list of donations to the 

 Herbarium, in which the plants and plant products are arranged 

 in alphabetical order, should prove of practical value. 



Three new volumes have lately appeared in the comprehen- 

 sive Aide-M6moire series published jointly by MM. Gauthier- 

 Villars and G. Masson, Paris. One is ' ' Applications 

 Scientifiques de la Photographic," by M. G. H. Niewenglowski. 

 We have long expected the publication of a book on this 

 subject, but the one now before us is satisfactory. No account 

 is given of the remarkable results obtained in astronomical 

 photography, and the photography of solar and stellar spectra 

 is only mentioned in a few words. In fact, the author has not 

 treated his subject in the broad scientific manner it deserves, 

 and there is yet room for some one to write a really good treatise 

 on it. The volume by M. X. Rocques entitled " Analyse des 

 Alcools et des Eaux-de-vie," just published in the same series, 

 should prove of service to analytical chemists ; while the third 

 of those lately received — '* La Topographic," by Lieut. -Colonel 

 P. Moessard, is an excellent manual on maps and their construc- 

 tion, containing concise descriptions of triangulation, levelling, 

 and cartography. 



The last number of the Bollettino of the Italian Seismological 

 Society contains an interesting paper by Dr. G. Agamennone, on 

 the earthquake of Paramythia (Epirus) during the night of May 

 13-14, 1895. The official accounts state that 269 houses were 

 destroyed, and 262 more were rendered uninhabitable ; that 

 seventy persons were killed and fifty wounded ; but Dr. 

 Agamennone believes that these figures refer only to the district 

 of Paramythia. The area including all the villages where houses 

 were damaged is elliptical in form and contains about 400 

 sq. km., the longer axis being directed N.N.E. and S.S.W. 

 The centre of this area lies near the villages of Dragani and 

 Carvounari, where the intensity of the shock was between ix. 

 and X. of the Rossi-Forel scale. In this district, the ground 

 was fissured in several places. The shock was felt, though 

 slightly, at Zante, which ij 180 km. from the epicentre ; and the 

 pulsations were registered by several of the Italian seismographs, 

 and also by the horizontal pendulum at Nicolaiew, about 1250 

 km. from Paramythia. 



The additions to the Zoological Society's Gardens during the 

 past fortnight include a Burchell's Zebra {Equus burchelli, ? ) 

 from South Africa, presented by the Hon. W. Rothschild ; a 

 Common Badger (Meles taxus), British, presented by Mr. 

 Thomas B. Place ; a Rough Fox ( Cam's rudis) from Demerara, 

 presented by Captain J. Ernst ; a Blue and Yellow Macaw 

 i^Ara ararauna) from Brazil, presented by Mrs. Alec. Tweedie ; 

 two Hoary Snakes {Coronella cana), two Puff Adders {Vipera 

 arietans) from South Africa, presented by Mr. J. E. Matcham ; 

 an Anamolous Snake {Coronella anamola) from Brazil, presented 

 by Mr. Frank Summers ; a Nilotic Monitor ( Varanus niloticus) 

 from North Africa, deposited ; two Ornamental Lorikeets 

 ( Trichoglossus ornaius) from Moluccas, two Forsten's Lorikeets 

 (Trie hoglossus for steni) from Sumbawa, purchased; a' Cactus 

 Conure (Conurus cactorum) from Brazil, received in exchange ; 

 a Southern River- Hog (Potamoc/uertis africanus) from East 

 Africa, presented by Mr. Henry M. C. Festing ; a Golden 

 Eagle {Aquila chrysactus) from Scotland, presented by Mr. 

 Osgood H. Mackenzie ; a White-crowned Mangabey (Cercocebus 

 (BthiopSyS), a Green Monkey {Cercopithecus callitrichus, i ) 

 from West Africa, deposited ; two Red-sided Tits (Parus 

 varius) from Japan, purchased. 



