546 



NATURE 



[April 7, 1898 



The " Statesman's Year-Book," edited by Dr. J. Scott Keltic, 

 with the assistance of Mr. I. P. A. Renwick, annually improves 

 in Gharacter and increases in usefulness. The volume just pub- 

 lished by Messrs. Macmillan and Co. is the thirty-fifth ; and it 

 contains in the 1166 pages the latest statistical and other data 

 referring to all the States of the world. The special features 

 this year are maps showing, by means of different colours, the 

 distribution of British commerce throughout the world, a map 

 illustrating the Niger question, and a series of coloured dia- 

 grams exhibiting the course of trade in leading countries during 

 the past twenty-five years. Trustworthy information upon all 

 questions of political and commercial geography can be obtained 

 from the volume, which keeps its place as the most handy and 

 complete annual of geographical statistics in existence. 



The additions to the Zoological Society's Gardens during the 

 past week include a Molucca Deer (Cervus molticcensis, $ ) from 

 the Molucca Islands, presented by H.G. the Duke of Bedford ; 

 a Great-billed Touracou ( Turacus inacrorhynchus) from West 

 Africa, presented by Mr. R. J. Nicholas ; two Cambayan 

 Turtle Doves ( Turtur senegalenis) from West Africa, presented 

 by Sir Edward Burne-Jones ; a Macaque Monkey {Macacus cyno- 

 molgus) from India, presented by Captain Francis W. Bate ; 

 two Arctic Foxes {Cams lagopus) from the Arctic Regions, four 

 Oyster-catchers {Hiematopus ostralegtis), European, purchased ; 

 a Caucasian Wild Goat {Capra caucasica, <J,juv.) from the 

 Caucasus, received in exchange ; a Burchell's Zebra {Eijuus 

 burchelli, 9 ), born in the Gardens. 



OUR ASTRONOMICAL COLUMN. 



Spectrum Analysis of Meteorites. — A research of 

 great interest has been undertaken by Messrs. W. N. Hartley 

 and Hugh Ramage on the wide dissemination of the rarer 

 elements and the mode of their association in the more common 

 ores and minerals. The outcome of this work has led us to 

 believe that the rarer metals are more widely distributed than 

 was ever dreamt of, the authors showing that out of ninety-one 

 iron ores obtained from the Dublin Royal College of Science, 

 thirty-five contained the extremely rare metal gallium, while 

 most of them contained constituents of an unusual character. 

 Thus rubidium was commonly present : the magnetites invariably 

 contained gallium, but no indium ; the siderites all contained 

 indium, but lacked gallium. In a more recent research they 

 have investigated spectroscopically numerous meteoric ores, 

 siderolites and meteorites {Scientific Proc. of the R. DtcblinSoc, 

 vol. viii. (N.S.) Part vi.. No. 68), the range of spectrum being 

 between the wave-lengths 6000 and 3200, and the results they 

 obtained in this case, arranged in tabular form, are of great 

 interest. It is shown that the composition of different meteoric 

 irons is very similar, though the proportions of constituents 

 differ somewhat. Meteoric irons, different varieties of iron 

 ores, and manufactured irons contain copper, lead, and silver. 

 Gallium is a constituent of meteoric irons, but not of all 

 meteorites, and occurs in varying proportions. Sodium potas- 

 sium and rubidium are constituents of meteoric irons, but only 

 in very small proportions. Meteoric stones, but not the irons, 

 contain chromium and manganese. Nickel was found to be a 

 principal constituent in all meteorites, meteoric irons, and 

 siderolites, cobalt occurring in the two last varieties. The 

 authors describe the chief points of difference between telluric 

 and meteoric iron to be the absence of nickel and cobalt in any 

 considerable proportion from the former, and the presence of 

 manganese. Meteoric irons, on the other hand, contain nickel 

 and cobalt as notable constituents, and, except in minute traces, 

 manganese is absent. In referring to the photographic spectra 

 of iron meteorites obtained by Sir Norman Lockyer from the 

 Nejed and Obernkirchen meteorites, the authors point out that 

 of the two lines, one described as " unknown," and the other as 

 "doubtfully ascribed to iron," the former is certainly, and the 

 latter probably, a gallium line. At the conclusion of their paper 

 the authors give three plates, which reproduce the flame spectra 

 of six metallic irons and three siderolites with comparison spectra. 



Stellar Parallaxes. — Dr. Bruno Peter, during the years 

 1887 to 1892, made a series of parallax observations with the 

 Leipzig heliometer. The results of this investigation have 

 been published in vol. xxii. No. 4, and xxiv. No. 3, of the 

 Abhandlungen der Math.-Phys. Classe der K.S. Gesel. der 

 Wissenschaften ; but Dr. Peter makes a short abstract in the 

 Astronomiiche Nachrichten, No. 3483, which we briefly refer to 

 here. In the following table, which brings together these 

 results very clearly, « represents the mean error of the parallax, 

 and e' that for one evening. In the three references to the star 

 Lai 181 15, (i) relates to the preceding component, and (2) to 

 the following one, while (3) deals with the pair as a whole. 

 The last column gives the comparison stars employed in each 

 case. 



Comparison stars. 



+S7'"2 

 53207 

 31 •1648 



+ 57 172 

 54"24i 



301620 



53*1309 53"i33<> 



521389 

 50*1707 



28'2207 

 1 1 '3802 

 56 "2956 



5fi536 

 49-1946 



28-2184 

 12-3929 

 56-2978 



NO. 1484, vaL. 57] 



JAMES WATT, AND THE DISCOVERY OF 

 THE COMPOSITION OF WATER.^ 



V^HEN your Secretary did me the honour to communicate the 

 wish of the Committee that I should deliver this lecture, he 

 was good enough to send me a list of the names of my prede- 

 cessors in the position I was invited to occupy, together with a 

 statement of the .subjects on which they had addressed you. I 

 confess I read his letter with very mingled feelings. To be 

 asked to form one of such a distinguished company was in itself 

 an honour which I deeply appreciated. On the other hand, it 

 seemed well-nigh hopeless to find any theme associated with the 

 life and work of the great man whose services to humanity we 

 are this day called upon to commemorate, that had not been 

 dealt with by one or other of those who preceded me. Naturally, 

 and as befits the subject, the greater number of those who have 

 spoken on these occasions have been distinguished engineers and 

 mechanicians, and they have been able to speak with a fulness of 

 knowledge, and a weight of authority, on the outcome of the 

 great engineer's labours to which I, who know nothing of en- 

 gineering or machinery, can have no pretensions. 



It occurred to me, however, on reflection, that there was one 

 incident in Watt's career, which, so far as I could learn, had not 

 been handled by any one of those whom you have invited to 

 appear here, and to which, as it comes within my own province, 

 I thought I might venture, without presumption, to engage your 

 attention. I was the more impelled to select it in that it illus- 

 trates one side of Watt's intellectual activity which those who 

 regard him only as an inventor and a mechanician are apt to 

 undervalue or lose sight of altogether. It serves, too, to throw 

 additional light upon his mental character and moral worth, and 

 thus enables us to form a fuller and more just appreciation of the 

 attributes of the man we wish to honour. The incident, in a 

 word, relates to Watt's share in the establishment of the true 

 view of the chemical nature of water. 



To the historian of science this is doubtless an old story, on 

 which it would be difficult to say anything new. The literature 

 concerned with it occupies many volumes, largely owing to the 

 circumstance that it has given rise to a controversy which has 

 engaged the active interest of some of the strongest and subtlest 

 intellects of this century. Some of the disputants have been men 

 like Brougham, Jeffrey and Muirhead, skilled in the arts of 

 advocacy and in the faculty of eliciting and weighing evidence, 

 who have stated their conclusions with all the " pomp and cir- 

 cumstance " of a judicial finding ; others are men like Arago, 

 Dumas, HarcoUrt, Whewell, Peacock, Kopp, George Wilson, 



' The Watt Memorial Lecture, delivered in the Watt Memorial Hall' 

 Greenock, on March ii, by Prof. T. E. Thorpe, LL.D., F.R.S. 



