336,^ 



NATURE 



[February 4, 1892 



with water saturated with common salt the evaporation is 15 per 

 cent, less than with rain water. In his experiments Mr. Latham 

 used an evaporating gauge made of copper, i foot in diameter, 

 and containing i foot in depth of water, which was floated by 

 means of a hollow copper ring placed 6 inches distant from the 

 body of the evaporator, and attached to it by four radial arms. 

 This form of evaporator was found extremely convenient in 

 carrying on all evaporation experiments ; it was floated in a 

 tank 4 feet in diameter, containing 30 inches depth of water. 

 During the period of thirteen years, from January 1879 to 

 December 1891, this evaporator has never once been out of 

 order, or been interfered with in the slightest degree by frost. 

 Experiments were made with some 5-inch evaporators as to the 

 effect of colour on the amount of evaporation, one being painted 

 white, another black, and the results given by these gauges were 

 compared with a copper gauge exposed under similar conditions. 

 This comparison was the means of showing that the greatest 

 errors in evaporating gauges arise from the capillarity of the 

 water rising on the sides of the gauge, and thus inordinately in- 

 creasing the amount of evaporation. Consequently a small 

 gauge having a larger amount, in proportion, of side area than 

 a larger gauge, gives a very much greater amount of evaporation. 

 The results from the floating evaporator, i foot in diameter, 

 show that the average amount of water evaporated annually 

 during 1879-91 was I9"948 inches. It was found, however, 

 that, as a rule, during the period from October to March, there 

 were certain occasions when condensation was measured. The 

 amount of these condensations in thirteen years averaged "308 

 inch per annum. The 5-inch evaporating gauge, freely exposed 

 to atmospheric influences, gave during the same period (1879-91), 

 an average annual depth of evaporation equal to 38'l85 inches. 

 The average annual evaporation, during the three years 1879-81, 

 from the 5-inch copper gauge standing in water was 27*90 

 inches, from one painted black 22*97 inches, and from another 

 painted white 2174 inches, whilst a gauge of the same dimen- 

 sions, freely exposed in the atmosphere, gave, in the same 

 period, 36*96 inches, and the i foot floating evaporator, 19*40 

 inches. The 5-inch copper gauge gave a larger amount of 

 evaporation than the gauge painted black. — Mr. Latham next 

 described some percolation experiments which were carried out 

 by Mr. C. Greaves at Old Ford, by Messrs. Dickinson and Evans 

 at Hemel Hempstead, and by Sir J. B. Lawes and Dr. Gilbert 

 at Rothamsted. He then detailed the results of his own ex- 

 periments, and also the gaugings of the underground waters in 

 the drainage areas of the rivers Wandle and Graveney. He 

 further stated that in the course of his observations on the flow 

 of underground water, he had observed that at certain particular 

 seasons of the year it was possible to indicate the direction and 

 volume of the flow of underground streams, even when they 

 were at a considerable depth, owing to the formation of peculiar 

 lines of fog. — Dr. C. Theodore Williams was elected President 

 for the ensuing year. 



Paris. 

 Academy of Sciences, January 26.— M. Duchartre in the 

 chair. — On the properties of the loxodromics of a cone of revo- 

 lution, and their application to the conical spring, by M. H. 

 Resal. — /v'«?/w/ of solar observations made at the Royal Obser- 

 vatory of the Roman College during the last quarter of 1891, by 

 Prof. Tacchini. Spots and facula; show a slight diminution 

 when their frequency is compared with that of the preceding 

 quarter. On no day, however, has the sun been observed free 

 from spots. — Experimental study of the decimal equation in 

 transit observations, made at Lyon Observatory, by MM. Andre 

 and Gonnessiat. — On a real algebraical curve with constant 

 torsion, by' M. E. Fabry. — On the characteristic equation of 

 water-vapour, by M. Ch. Antoine. The author shows that the 

 weight, ffi, of a cubic metre of water-vapour at a temperature /, 

 and under a pressure H, is given by the relation 

 a = '9-9H 



278 - 0*3656 + t 

 in which represents the temperature of the vapour at satura- 

 tion under the pressure H. — Remarks on the subject of the 

 experiments made by M. Gouy on the difference of potential 

 produced by contact, by M. H. Pellat. — On Hertz oscillations, 

 by M. A. Perot. In a recent work {Wiedemann's Ann., xliv. 

 pp. 74 and 92) Bjerknes shows that the oscillations of electro- 

 motive force produced in a conducting wire by Hertz's 

 method ought to be represented by the equation — 



Y = A^-«('-e)sin tt/'- - <^\ 

 NO. I 162, VOL. 45] 



M. Perot finds that the formula proposed is supported by ex- 

 periments.— On aplanatism, by M. A. Broca.— The estimation 

 of molybdenum, by M. E. Pechard. The compound contain- 

 ing the molybdenum is heated in a current of HCl, when 

 MoO<,.2HCl volatilizes, is collected, dissolved in water, with 

 the aid of nitric acid if any of the blue reduction compound is 

 formed, and the solution evaporated to dryness ; the molybdic 

 acid is then weighed. — On the stereochemical constitution of 

 diacetyltartaric acid, by M. Albert Colson. — On some soluble 

 colouring- matters produced by bacteria in medicinal distilled 

 waters, by M. L. Viron. — On the existence of nitrification phe- 

 nomena in media rich in acid organic substances, by M. E. 

 Chuard. — Ammonia in rain-water and in the atmosphere, by 

 M. A. Muntz. — In a former paper the author stated that the 

 rain-water of tropical regions was richer in ammonia than that 

 of temperate climates. This conclusion was combated by M. 

 Levy, who showed that the proportion of ammonia in rain 

 caught at Montsouris was greater than that recorded by M. 

 Muntz. The latter gentleman now points out that the observa- 

 tions made at Montsouris, or near any populous district, do not 

 furnish proper criteria for the judgment of his first statement, — 

 Earthworms and the bacilli of tuberculosis, by MM. Lortet and 

 Despeignes. — On the inoculation of dourine, by M. Ed. Nocard. 

 — Researches on the nervous system of Crustacea, by MM. F. 

 Jolyet and H. Viallanes. — On the pelagic fauna of Dyrefjord 

 (Iceland), by M. G. Pouchet. — On an elliptical halo observed 

 around the moon on January 14, 1892 ; extract from a letter 

 addressed to M. Cornu by M. Hamy. 



BOOKS, PAMPHLETS, and SERIALS RECEIVED. 



Books. — L'EvoIution Sexiielle dans I' Espece Humaine ; Dr. H. Sicard 

 (Paris, J. B. Bailliere).— Les Problemes de la Geologic et de la PaMontologie : 

 T. H. Huxley (Paris, J. B. Bailliere). — Report on the Scientific Results of 

 the Voyage of H.M.S Challenger; Deep-Sea Deposits (Eyre and Spottis- 

 woode). — Treatise on Chemistry, vol. iii. Part : Sir H. E. Roscoe and C. 

 Schorlemmer (Macmillan). 



Pamphlets. — Guide to the Examinations in Chemistry and Answers to 

 Questions: W. J. Harrison (Blackie). — Guide to the Examinations in 

 Geology and Answers to Questions : W. J. Harrison (Blackie). 



Serials. — The London and Middlesex Notebook, vol. i. No. 4 (Stock). 

 — Bulletin de TAcadeinie Royale des Sciences de Belgique, No. 12, tome 

 22 (Bruxelles). — Quarterly Journal of the Geological Society, vol. xlviii. 

 Part I, No. 189 (Longmans). — Rendiconto dell' Academia dell' Scienze 

 Fisiche e Matematiche (Sezione della Societa Reale di Napoli), January- 

 December 1891 (Napoli). 



CONTENTS. PAGE 



Carpenter by Dallinger. By Prof. E. Ray Lankester, 



F.R.S 313 



Elementary Thermodynamics. By C. G. K 314 



The Century Dictionary 316 



Our Book Shelf:— 



Sclater : " List of the Snakes in the Indian Museum." 



W. T. B 317 



Conn: "The Living World : Whence it Came and 



Whither it is Drifting " 317 



Stuart: "Adventures amidst the Equatorial Forests 



and Rivers of South America 317 



Letters to the Editor:— 



Cirques.— Prof. G. Frederick Wright; Prof. 



Israel C. Russell . 317 



Large Meteors of January 24, 1892. — "W. F. 



Denning 319 



On the Relation of Natural Science to Art.— W. 



Ainslie HoUis 3^9 



Ice Crystals.— Gilbert Rigg 3^9 



A Tortoise inclosed in Ice.— Frank Finn 320 



Alpine Rubi.— T. D. A. Cockerell 320 



Utilization of Homing Pigeons. {Illustrated.) By 



W. B. Tegetmeier 320 



Notes 322 



Our Astronomical Column:— 



New Star in the Milky Way 325 



Observations of Mars 326 



Solar Prominence Photography 326 



Re-discovery of Brooks's Comet (1890 II.) 326 



Electrotechnics. By Prof. W. E. Ayrton, F.R.S. . 326 

 Photography as a Branch of Technology. By Prof. 



R. Meldola, F.R.S Zl^ 



University and Educational Intelligence 334 



Societies and Academies 335 



Books, Pamphlets, and Serials Received 336 



