264 



NA TURE 



[July 14, 1892 



60°, From a hygienic point of view it is of still more importance 

 . to discover what is the lowest temperature at which the bacilli 

 of tuberculosis are destroyed. It is established that tuberculosis 

 is produced by the consumption of milk secreted by tuberculous 

 cows. Meat also, coming from tuberculous cattle, sometimes 

 contains infectious matter. By boiling heat, indeed, the bacilli 

 of tuberculosis are killed. But if meat is prepared in the usual 

 manner, even small pieces of it are not warmed thoroughly at 

 100° C. ; milk, on the other hand changes in taste if boiled, so 

 that most people do not like boiled milk. By a series of experi- 

 ments, recently made. Prof. Forster has settled that the bacilli 

 of tuberculosis are destroyed by a temperature of 60° C. acting 

 during one hour, and by the action during six hours of a tem- 

 perature of 55° C. Higher temperatures than 60°, for instance, 

 80, 90 or 95" C, destroy the infectious matter in milk from 

 tuberculous cows, if they act during ten minutes ; "pas- 

 teurizing," however, at 80° during one minute does not hurt the 

 bacilli of tuberculosis, (2) On the development of bacteria at 

 a temperature of melting ice. He had formerly demonstrated 

 cultivations of bacteria, which produce light of phospho- 

 rescence. The same kind of bacteria are also able to develop 

 and to multiply at a temperature of 0° C. He found that 

 bacteria which have this peculiar quality, so interesting from a 

 biological point of view, not only live in the sea, but are met 

 with in brackish and fresh water, upon victuals, manures, etc., 

 etc. This agrees with the fact that victuals, kept for some days 

 •in an ice-chamber, gradually assume a disagreeable smell and 

 taste ; and that meat can be preserved from putrefaction for 

 days but not for weeks. If foods are to be preserved at a low 

 temperature for a long time, beside cold a second agent is 

 necessary— dryness. In the cooling rooms of the most modern 

 establishments (slaughterhouses, stores, etc., etc.) no use is 

 made of ice, which after melting moistens the atmosphere and 

 the objects in the ice-chambers, but arrangements are made by 

 which the atmosphere is cooled to a low temperature and at 

 the same time kept perfectly dry. — M. Beyerinck spoke of the 

 culture of organisms of nitrification on agar-agar and on gelatine. 

 First it was stated, in accordance with the discovery of War- 

 ington and Winogradsky, that nitrification consists in two 

 processess — the formation of nitrous acid from the ammonsalt 

 by a specific bacterium and the oxidation of the nitrite into 

 nitrate by another and independent species of bacterium. 

 Secondly, that both these processes occur only when soluble 

 organic matter is reduced to a minimum such as has been proved 

 by the classic researches of Winogradsky and the Franklands. 

 Even o"i per cent, of calcium-acetate retards nitrification 

 strongly. Thirdly, it was found that organic matter in the 

 solid state does not in the least interrupt or retard nitrification. 

 Therefore an attempt was made — and successfully — to cultivate 

 the nitrous and nitric bacteria on agar-agar, fully extracted with 

 distilled water and afterwards boiled with the inorganic salts 

 needed for nitrification. If with these salts some pure pre- 

 cipitated carbonate of lime was added to the agar it was 

 possible to obtain a " chalk-agar-plate," whereon the nitrous 

 bacteria of the soil, after their growth into colonies, could 

 directly be numbered. P'or this purpose the chalk-agar is 

 poured into a glass-box, and some soil suspended in sterilised 

 water brought on the surface of the solidified plate. After 

 three to four weeks the colonies become visible as the centres of 

 clear, transparent, perfectly circular diffusion figures, formed 

 by the solution of the carbonate of lime in the nitrous acid, the 

 very soluble calcium-nitrite diffusing in all directions in the 

 agar-plate. In this way it was found, for example, that out of 

 c.a. 10 millogrammes soil taken from under a sod of white 

 clover in a garden at Delft, thirty colonies of the nitrous 

 bacterium could be cultivated. The species is the same as that 

 described as the European form by Winogradsky, growing, as 

 well as zoogloea, quite free, and possessing the form of a small, 

 moveable mikrokok with one cilium. Gelatine, prepared with 

 the same precautions as the agar, can also be used, but therein 

 the production of nitrous acid soon ceases. The nitrous 

 bacterium does not liquefy the gelatine. Though it does not 

 grow or oxidize when organic matter is present, it does not 

 lose these powers by this contact, as shown when brought anew 

 under adequate conditions. The nitric bacterium was also 

 isolated on lully extracted agar, to which O'l percent, potassium- 

 nitrite and some phosphate was added. The colonies are 

 very small and coloured light yellow. They consist of very 

 small non-moving mikrokoks or short ellipsoids. They lose 

 their power of oxidizing nitrites by the contact of soluble 



organic matter, without thereby losing their power of growth. 

 The nitric bacterium does not oxidize ammonsalts. It is also 

 without action on potassium rhodanate and hydrochloric- 

 hydroxylamine. It therefore does not seem to produce free 

 acid such as the nitrous bacterium. A simple method for the 

 formation of sterile plates of silica, with and without carbonate, 

 was also described. Many preparations were demonstrated. 



BOOKS AND SERIALS RECEIVED. 



Books. — Grasses : C. H. Jones (S.P.C K.). — A Synoptical Geography of 

 the World (Blackie). — London Matriculaticn Directory, No. xii., June 

 1892 (Clive)— The Case against Bimetallism: R. Giffen (Bell).— The Birds 

 of Devon: W. S. M. D'Urban and Rev. M. A. Mathew (Porter).— Uni- 

 versal Atlas. Part 16 (Cassell). — Photography Annual, 1892 (Uiffe). — 

 Museum d'Histoire Naturelle des Pays Basjtom'e xi.. Cat. Syst^matique 

 des Mammiferes : F. A. Jentink (Leide, Brill). — The Applications of 

 Elliptic Functions : A. G. Greenhill (Macmillan and Co.) — Sunshine : A. 

 Johnson (Macmillan and Co.). — Theory of Numbers, Part i : G. B. 

 Mathews(Hell).— Alcohol and Public Health: Dr. J. J. Ridge (Lewis).— 

 Murray's Hand-book ; Norway, 8th edition (Murray). 



Serials. — Transactions of the County of Middlesex Natural History and 

 Scientific Society, Sessions 1889-90, iSgo, and 1891 (London). — Natural 

 Science, No. 5 (Macmillan and (Jo.).— L' Anthropologic, 1892, tome 3, No. 3 

 (Paris, Masson). — Bulletin de I'Acad^mie Royale des Sciences de Belgique, 

 No. 5 (Bruxelles). — Journal of the Royal Agricultural Society of England, 

 3rd series, vol. 3, Part 2, No. x. (Murray). — Department of Agriculture, 

 Victoria, Bulletin No 14 (Melbourne). — The Asclepiad, No. 34, vol. ix. 

 (Longmans). — Mind, July (Williams and Norgate). — Journal of Anatomy 

 and Physiology, July (Williams and Norgate). — Archives des Sciences 

 Biologiques publiies par I'Jnstitut Imperial de M^decine Exp^rimentale k 

 St. P^tersbourg, tome i, No. 3 (St. Petersburg). — Geological Magazine, 

 July (K. Paul).— Annals of Scottish Natural History, No. 3 (Edinburgh, 

 Douglas). — Medical Magazine, vol. i, No. i (Southwood).— Journal of the 

 Royal Statistical Society, June (Stanford). — Journal of the Chemical 

 Society, July (Gurney and Jackson). — Quarterly Journal of Microscopical 

 Science, No. 132 (Churchill). 



CONTENTS. PAGE 



A Treatise on Zoology. By G. B. H 241 



Watts's "Dictionary of Chemistry." By Sir H. E, 



Roscoe, F.R.S. . . • 242 



The EngUsh Slojd 244 



Our Book Shelf: — 



J. Willard Gibbs : " Thermodynamische Studien " . 245 



C. E. Fessenden : " Elements of Physic" .... 245 

 M. Alheilig : " Recette, Conservation, et Travail des 



Bois" 246 



K, B. Baghot de la Bere : " Country Thoughts for 



Town Readers" 246 



" A Synoptical Geography of the World " 246 



Letters to the Editor : — 



An Acoustic Method whereby the Depth of Water in 

 a River may be measured at a Distance. — Frederick 



J. Smith 246 



Waterspouts in East Yorkshire.— J. Level 246 



On the Line Spectra of the Elements.— C. Runge . 247 



The Grammar of Science.— Karl Pearson . . . . . 247 



"Are the Solpugidse Poisonous?" — W. L. Distant 247 

 Hairlessness of Terminal Phalanges in Primates. — Dr. 



George J. Romanes, F.R.S 247 



Mental Arithmetic — G. Daehne 247 



Jackals.— Hyde Clarke 247 



Weight. By Prof. A. G. Greenhill, F.R.S 247 



Aphanapteryx and other Remains in the Chatham 



Islands. By Henry O. Forbes 252 



Admiral Mouchez 253 



Notes 253 



Our Astronomical Column : — 



Lunar Photography 257 



Comet Swift (i892>Iarch 6) 258 



Opposition of Mars 258 



Sun-Spots 258 



Remarkable Prominences 258 



Geographical Notes 258 



Easter Island 258 



Embryogeny of Gnetum. By A. W. B 200 



International Congress of Experimental Psychology. 



By F. W, H. Myers and James Sully 261 



Scientific Serials 262 



Societies and Academies 262 



Books and Serials Received , • • • 264 



NO. II 85, VOL. 46] 



