NATURE 



[August i8, 1910 



GREENWICH WATCH AND CHRONOMETER 



TRIALS. 

 " \\JHAT is the chief end of an astronomer?" is 

 *• not so stereotyped a question as the corre- 

 sponding conundrum respecting the chief end of 

 man. This question is, however, suggested by the 

 following statements in the last annual report of the 

 Astronomer Royal to the Board of Visitors : — " In the 

 year ending igio. May lo, the average daily number 

 of chronometers and watches being' rated (at Green- 

 wich) was 596." "The number of Government 

 marine chronometers and watches now at the Observa- 

 tory is 455." " For the annual trial of chronometers 

 . . . 66 . . . were sent in ... 8 were purchased for 

 the Navy and 4 for the Indian Government." " For 

 the annual trial of chronometer watches . . . 173 . . . 

 were entered . . . and ... 35 were purchased for 

 the Navy." In addition there was a trial of pocket 

 chronometers, seventeen being sent in and two pur- 

 chased for the Navy. The average number of 

 chronometers rated daily has, we learn, more than 

 trebled since 1880, so that the burden of this work 

 borne by the Observatory has enormously increased. 

 The work is doubtless most valuable for the Navy, 

 but is our great national Observatory exactly the place 

 where it should be done? 



The question is manv-sided. Science for its own 

 sake is regarded by the multitude as a most excellent 

 occupation for wealthy amateurs, but a State-sup- 

 ported institution is expected to devote itself to imme- 

 diately-practical ends. From this point of view it is 

 only work such as supplying the national time and 

 rating the national chronometers that justifies the 

 existence of Greenwich. There is thus some reason 

 to fear that if this and other obviously useful work 

 ceased, the continuation of the financial support from 

 Government that enables the Observatory to carry out 

 work that is more directly astronomical might be 

 jeopardised. On the other hand, whatever adds to 

 the burden of routine and administrative labour borne 

 by the Astronomer Royal, must reduce the time and 

 energy which he can devote to what is purely scien- 

 tific. 



There are several points of interest in the details 

 of the trials. The box chronometer trial lasted 

 twenty-nine weeks, from June ig, 1909, to January 8, 

 19 10, the temperatures to which the chronometers 

 were exposed varying from 458° to io5'6° F. The 

 chronometers are arranged in order of merit accord- 

 ing to the value of a + 2b, where a is the difference 

 between the algebraically greatest and least of the 

 weekly rates, and b the greatest difference in rate 

 between two successive weeks. As in golf, the lowest 

 score is the best. Pocket chronometers and chrono- 

 meter watches are let off with an eighteen-week trial, 

 notwithstanding the fact that, unlike the box chrono- 

 meters, thev are tried in a number of positions. Their 

 place on the list is determined by a formula which 

 takes account of the differences between the rates in 

 the several positions. Even eighteen weeks is a long 

 time compared to the duration of watch trials at the 

 Swiss observatories, at Besancon or at Kew. 



The chief obstacle to uniformity of rate, especially in 

 box chronometers, is the effect of temperature, but a 

 much shorter trial than twenty-nine or eighteen weeks 

 would suffice to test the behaviour of the temperature 

 compensation. The main object, presumably, in hav- 

 ing so long a trial is to afford an opoortunity for any 

 weak point to declare itself. On this question one 

 would like to know the views, both of the makers 

 and of the Observatory authorities. A long trial 

 means a lock-up of capital, which must presumably 

 have an effect on the cost, especially as' only a frac- 

 NO. 2129, VOL. 84] 



tion — in the present case apparently only a small 

 fraction — of the chronometers and watches were actu- 

 ally purchased for the Navy. In the present day, with 

 the increase of speed, a ship is seldom isolated for any 

 great length of time, and the breakdown of a single 

 chronometer is unlikely to be a serious matter. Thus 

 the case for a long trial does not seem so strong as 

 it may have been a generation ago. Very probably 

 ere long the development of wireless telegraphy may 

 alter the whole situation. 



NOTES. 



A FINE specimen of a rare class among the scientifically 

 eminent passed away when the Rev. Robert Harley, 

 F.R.S., died on July 2G, in his eighty-third year. Many 

 friends will miss his hale face and hearty greeting at 

 meetings of the Royal Society ; and few of them can have 

 had any idea that one so keen in his interest could be 

 an octogenarian. Mathematics with him was a parergon, 

 almost a hobby. He achieved distinction in it in early 

 middle life, pursuing it in scanty intervals of leisure 

 secured without neglect of engrossing non-scientific duties. 

 The son of a Methodist minister, he had no early mathe- 

 matical training. At the age of twenty-three he entered 

 .Airedale College as a student of theology, and shortly 

 afterwards he was ordained as pastor of the Congrega- 

 tional Church at Brighouse, Co. Vorks. Here he found 

 time to become a mathematician of mark. The applica- 

 tion of mathematics to logic as developed by George Boole 

 captivated his intelligence, and he became the most notable 

 of Boole's admirers and followers, as also his biographer. 

 His greatest mathematical achievements were, however, 

 in another field. The unsolved problem of the solution of 

 quintic equations fascinated him. Having once granted the 

 impossibility of the solution by radicals, he proceeded to 

 exhibit with remarkable power and patience the place of 

 certain sextic resolvents in connection with such equations. 

 .Simultaneously, the late Sir James Cockle was engaged on 

 like work ; but Harley was the clearer writer on the 

 difficult subject. Their work, and in particular Harley's, 

 was welcomed enthusiastically by Cayley, who himself took 

 it up and continued it. All three probably were not aware 

 at the time that certain Continental writers had possessed 

 some of their ideas beforehand ; but everyone must 

 recognise that Harley's development of the ideas was 

 masterly. It secured for him the Fellowship of the Royal 

 Society in 1863. Since then, as before, he carried on 

 mathematical research only in such time as was allowed 

 by devotion to pastoral, philanthropic, and temperance 

 work. He laboured in Leicester, Oxford (where he was 

 an original member of the Oxford Mathematical Society, 

 and was given the honorary degree of Master of Arts by 

 the University), Halifax, and elsewhere. From 1872 until 

 1881 he was vice-principal (and chaplain) of Mill Hill 

 School. For the three years before his removal to O.xford 

 in 1886 he was principal of Huddersfield College. In 

 1890 he took a period of rest (with pastoral work) in 

 Sydney, .Australia. Since 1895 his life was one of retire- 

 ment, but far from one of inactivity, whether religious, 

 benevolent, or scientific. 



Thf, Berlin correspondent of the Times announces the 

 death, in his seventy-si.xth year, of Prof. A. Michaelis, 

 who until three years ago was, since 1872, professor of 

 classical archaeology at Strassburg University. In addition 

 to being the author of a large number of works on archaeo- 

 logical subjects. Prof. Michaelis organised the admirable 

 archxological museum of Strassburg University. 



