30 



NATURE 



[March 13, 1919 



pied, in conjunction with the late J. W. Rodger, 

 on an elaborate investigation of the magnetic 

 rotation of the plane of polarisation in liquids (Phil. 

 Trans., 1895, pp. 621-54), which has not yet been 

 surpassed. A research of a similar character by 

 an original method, on the determination of the 

 earth's magnetic field (Phil. Trans., 1902, pp. 

 431-62), threw great light on some of the sources 

 of error in absolute magnetic measurements. 



While engaged in these researches, and taking 

 his full share of the teaching work, Watson yet 

 found time to write his well-known " Text-book 

 of Physics," which has become deservedly 

 popular, and has made his name familiar to an 

 ever-increasing circle of students. As a teacher 

 his clearness of exposition and his skill in devising 

 experimental illustrations made his lectures very 

 attractive to the serious student. 



A large part was taken by Watson in the design 

 and equipment of the new laboratory (now part of 

 the Imperial College) to which the physics de- 

 partment of the Royal College was transferred 

 in 1905. He next became interested in the appli- 

 cation of physical methods to the scientific study 

 of the petrol motor, and devised many ingenious 

 instruments of research, including a new type of 

 optical indicator, which has proved invaluable for 

 accurate work on high-speed engines. The labora- 

 tory which he designed and equipped for these 

 experiments has since been taken over and ex- 

 tended by the Air Ministry, and proved very 

 useful during the war for the solution of urgent 

 problems in connection with aero-engines. Many 

 of his results were of fundamental importance, and 

 will be found in most standard treatises on the 

 subject. 



Watson assisted Sir W. de W. Abney for many 

 years in his researches on colour vision, and 

 made useful contributions of his own to the theory 

 and methods of measurement, a characteristic 

 example of which will be. found in his paper on 

 luminosity curves (Proc. R.S., 88 A, p. 404, 1913). 

 In a later paper Sir W. Abney indicates that they 

 were busily engaged on work of great promise in 

 this direction when Watson was "commandeered 

 as scientific adviser at the front." The work 

 which he accomplished in this capacity was doubt- 

 less of the greatest national importance, but, in 

 the interests of pure science, one cannot help 

 regretting that so active and many-sided an in- 

 vestigator should have been cut off in his prime 

 by the relentless exigencies of war. 



NOTES. 



After two years' interval, owing to war conditions, 

 the British Association for the Advancement of 

 Science will resume its series of annual meetings 

 this year at Bournemouth from September 9 to 13, 

 under the presidency of the Hon. Sir Charles 

 Parsons. 



Sir George Newman, K.C.B., Chief Medical 

 Officer, Local Government Board, has been elected 

 a member of the Athenaeum Club under the rule 

 which empowers the annual election by the com- 



NO. 2576, VOL. 103] 



mittee of a certain number of persons "of distin- 

 guished eminence in science, literature, the arts, or 

 for public service." 



At the quarterly Court of the governors of the 

 London Hospital, held on March 5, Lord Knutsford 

 made the important announcement that it is proposed 

 to fill up two vacancies on the honorary visiting staff 

 by the appointment of two whole-time adequately 

 paid officers in charge of the beds. Under the new 

 arrangement there would be a director, three clinical 

 assistants, and laboratory and clerical assistants. 

 These members of the staff will give their whole time 

 to curing disease, to researches on the causation of 

 disease, and to the education of the medical students, 

 and they will be of precisely equal rank with the other 

 members of the honorary staff. It will be remem- 

 bered that this kind of arrangement was suggested 

 in the report of the Haldane University Commission, 

 and has been commended by Sir George Newman in 

 his "Notes on Medical Education." 



The ravages of the larvae of ox warble-flies are 

 well known to farmers, butchers, hide-dealers, and 

 tanners. The flesh of bullocks and the milk yield of 

 cows suffer through the presence of these parasites, 

 and the piercing of the hides greatly reduces the value 

 of the latter. Furthermore, the annoyance caused 

 by the flies during a hot July or August prevents 

 cattle from thriving so well as they otherwise would 

 do. So far little or no good results have been 

 achieved from the application of various dips and 

 smears which are intended to prevent oviposition by 

 the flies. The only measure that can be advocated 

 with any confidence is the systematic destruction of 

 the larvae in the backs of the cattle. This method 

 has the obvious disadvantage that the parasite is 

 destroyed only after it has wrought its injuries. Im- 

 pressed by the damage caused by the fly, the War 

 Office called a conference last July of Government 

 Departments, men of science, traders, and others 

 familiar with the pest to discuss measures for its 

 extermination. A scientific sub-committee, presided 

 over by Sir Stewart Stockman, will supervise experi- 

 mental researches. A Government grant has been 

 sanctioned, and the experiments are designed to fur- 

 nish information on methods of preventing egg-laying 

 of the fly, and on the effects of drugs in destroying 

 the larvae in the body of the host before they com- 

 mence to penetrate the hide. 



The predominant character of the weather over the 

 British Isles since the commencement of the year 

 has been rainy and dull. The rainfall in January 

 exceeded the average over the whole kingdom except 

 in Scotland N., where there was a deficiency of 

 about 2 in. At Bournemouth the rainfall was 

 252 per cent, of the normal, at Arundel 236 per cent., 

 and in London, at Camden Square, 176 per cent. At 

 Kew Observatory the excess of rain was 1-77 in., at 

 Southampton 224 in., and at Falmouth 2-86 in. 

 February rainfall was in excess of the average in 

 the south and east of England, and deficient else- 

 where. At Greenwich the excess of rain was 075 in., 

 at Cambridge 1-85 in., at Southampton 232 in., and 

 at Falmouth 280 in. In the first ten days of March 

 rains were generally heavy; at Greenwich, in the 

 three days ending March 5, the rainfall measured 

 1-49 in., which is 0-03 in. more than the sixty years' 

 average for the whole month. The aggregate dura- 

 tion of bright sunshine since the commencement of 

 the 3'ear has been deficient in all districts of the 

 British Isles except in Ireland and in Scotland N. ; 

 in the south-east district of England the deficiency 

 amounts to o-6h. daily for the first nine weeks, or 



