June 23, 1921] 



NATURE 



541 



Calendar of Scientific Pioneers. 



June 23, 1881. Matthias Jakob Schleiden died. — At 



first an advocate at Hamburg, Schleiden afterwards 

 held the chairs of botany at Jena and Dorpat. He 

 did much to establish the cell theory, while among 

 his important writings was his " Principles of Scientific 

 Botany." 



June 23, 1891. Wilhehn Eduard Weber died.— Pro- 

 fessor of physics in the University of Gottingen, 

 Weber was associated with Gauss in some of his 

 investigations, and did valuable work on the defini- 

 tion and determination of electrical units. 



June 23, 1896. Sir Joseph Prestwich died. — While 

 in business as a London wine merchant, Prestwich 

 studied the geology of Hampshire and the London 

 basin, the coal supply of England, and the antiquity 

 of man. At the age of sixty-two he succeeded 

 Phillips as professor of geology at Oxford. 



June 25, 1868. Carlo Matteucci died. — The recipient 

 in i8-i4 of the Copley medal for his electrical re- 

 searches, Matteucci was professor of physics, first at 

 Bologna, and then at Ravenna and Pisa. For some 

 years he was connected with the Italian telegraphs. 



June 26, 1793. Gilbert White died. —Educated at 

 Oxford, and for a time senior proctor. White passed 

 most of his life at Selborne. His well-known 

 "Natural History and Antiquities of Selborne" was 

 published in lySq. 



June 26, 1831. Sophie Germain died. — S. versatile 

 and learned woman, Sophie Germain was distin- 

 guished for her mathematical writings on elastic 

 surfaces. 



June 26, 1SS3. Sir Edward Sabine died. — An officer 

 in the Royal Artillery, Sabine made valuable pen- 

 dulum and magnetical investigations which gave an 

 impulse to the systematic study of terrestrial mag- 

 netism. From 1 86 1 to 1871 he was president of the 

 Royal Society. 



June 27, 1829. James Smithson died. — Owing to 

 circumstances of birth, Smithson was educated at 

 Oxford under an assumed name. His knowledge of 

 chemistry and mineralogy led to his being admitted 

 as a fellow of the Royal Society in 1787. Most of his 

 life was spent on the Continent, associating and cor- 

 responding with men of science. He died at Genoa, 

 leaving his fortune of more than iqo,oooZ. to the 

 United States, the Government of which founded the 

 famous Smithsonian Institution. 



June 27, 1876. Christian Gottfried Ehrenberg died. 

 — After travelling through East Russia with Hum- 

 boldt, Ehrenberg became a jirofessor at Berlin, and 

 in 1842 was made secretary to the Berlin Academy 

 of Sciences. He was the first to show that certain 

 rocks consisted of minute forms of animals or 

 plants. His " Mikrogeologie " was published in 1854. 



June 27, 1892. Carl Schorlemmer died. — .A student 

 of Bunsen's, Schorlemmer in 1858 came to England 

 as assistant to Roscoe, and in 1874 was appointed 

 professor of organic chemistry at Manchester. 



June 28, 1897. Paul Schutzenberger died. — The suc- 

 cessor of Balard at the College de France, Schutzen- 

 berger made important researches on colouring 

 matters, the constitution of alkaloids, and on platinum 

 compounds. 



June 29, 1895. Thomas Hrnry Huxley died. — .As a 

 naval surgeon Huxley cruised in H.M.S. Rattlesnake, 

 and sent home important papers on the Hydrozoa. 

 From 1854 ^" 1885 he was professor of natural his- 

 tory at the School of Mines. His scientific work em- 

 braced vertebrate and invertebrate morphology, corn- 

 parative anatomy, histology, and palaeontology. His 

 lucid essays and crusade for freedom of thought 

 attracted widespread attention, and as "a man and a 

 citizen " he undertook much public work. E. C. S. 



NO. 2695, VOL. 107] 



Societies and Academies. 



LONDO.N. 



Royal Society, June 16.— Prof. C. S. Sherrington, 

 president, in the chair. — H. B. Dixon, Dr. C. Camp- 

 bell, and Dr. A. Parker : The velocity of sound in 

 gases at high temperatures, and the ratio of the 

 specific heats. — Prof. J. R. Partington : The ratio of 

 the specific heats of air and of carbon dioxide. The 

 ratio of the specific heats, 7 = c_,,/r_„ has been deter- 

 mined by the method of adiabalic expansion for the 

 gases air and carbon dioxide. The gas was contained 

 in a 120-litre vessel, and the temperature change im- 

 mediately after expansion followed by a platinum 

 thermometer, with compensating leads of wire 

 0001 mm. diameter, the resistance of which was 

 observed by an Einthoven string galvanometer of 

 001 seconds period. The fundamental temperature 

 measurements were made by a mercury thermometer. 

 The results were calculated by the characteristic 

 equation of D. Berthelot, so that deviations from* 

 the ideal gaseous state were allowed for. The final 

 results, accurate to i part in 1000, are : 7 for air at 

 17° C. = 1-4034; Y for carbon dioxide at 17° C.= 

 13022, whence c-p for air at 17° C. =02387 cal. and 

 f_p for carbon dioxide at 17° C.=oi996 cal. All the 

 values refer to atmospheric pressure. — Dr. /\. B. 

 Wood and Dr. F. B. Young: (i) • Light-body " hydro- 

 phones and the directional properties of microphones. 

 A light prolate ellipsoid possesses directional proper- 

 ties by virtue of its shajje. Quantitative results ob- 

 tained agree with calculated values supplied by Prof. 

 Lamb. Owing to the pronounced intrinsic directional 

 properties of the microphone, a spherical "light-body " 

 hydrophone is practically equal in directional efficiency 

 to one of ellipsoidal form. "Light-body" hydro- 

 phones are of value as experimental exploring instru- 

 ments. (2) The acoustic disturbances produced by 

 small bodies in plane waves transmitted through 

 water, with special reference to the single-plate direc- 

 tion finder. Sound distribution was explored round a 

 number of discs immersed at a distance from a small 

 submerged source of sound. By means of a pair of 

 miniature hydrophones — one bi-directional, the other 

 non-directional — it was possible to chart (i) direction 

 of oscillation of the water particles ; (2) relative ampli- 

 tude of the movements ; and (3) relative amplitudes of 

 the pressure oscillations. The charts obtained fall 

 broadly injo two classes, according as the discs are 

 solid or contain air-filled cavities, very minute air-filled 

 spaces giving marked effects. The behaviour of a 

 typical baffle-plate is investigated, but no satisfactory 

 theory of the baffle is offered.— M. A. Giblett : Some 

 problems connected with evaporation from large ex- 

 panses of water. The problems of distribution and 

 amount of water-vapour present are considered for a 

 current of air of uniform speed moving over a water- 

 surface of uniform temperature. Near the surface is 

 a thin layer of air, through which water-vapour dif- 

 fuses slowly bv molecular processes, but above this 

 is a rapid transition to a turbulent regime, where 

 diffusion becomes much more rapid. At and near the 

 water-surface the problem is treated as one of eddy 

 diffusion. Formulae are obtained for humidity at any 

 point of the air-current, and for rate of evaporation 

 from stretches of water extending any distance down- 

 wind. The distribution of water-vapour is obtained 

 for some typical cases, and an estimate made of the 

 rate of evaporation from long stretches of water under 

 various conditions of wind, water-surface, tempera- 

 ture, and turbulence. The effects which each of these 

 elements exerts, when varied within their natural 

 range, are examined. The results emphasise the con- 

 trol exercised by atmospheric turbulence over evapora- 



