Feb. 20, 1890] 



NATURE 



371 



oxide coat is a case of solid diffusion, and as such it 

 bears the same relation to the diffusion of liquids, that 

 the viscosity of solids bears to the viscosity of liquids. 

 The two phases (solid, liquid) of each phenomenon are 

 to be correlated in ways essentially alike. The available 

 stress, as compared with the available instability at a 

 given temperature, determines the time character of the 

 result. Carl B.\rus. 



Physical Laboratory, U.S. Geological Survey, 

 Washington, D.C. 



CHRISTOFORUS HENRTCUS DIEDERICUS 

 BUYS BALLOT. 



"OUYS BALLOT was born on October 10, 18 17, at 

 -*-' Kloetinge in Zealand ; was a student in arts and 

 the natural sciences at the University of Utrecht, where 

 he first became Lector of Physics and Chemistry in 1844, 

 and then successively Professor of Mathematics in 1847, 

 and of Experimental Physics in 1870, which latter chair 

 he ceased to hold in November 1887 on completing his 

 fortieth year as Professor. He was appointed Director of 

 the Royal Meteorological Institute of the Netherlands in 

 1854, and held this position with great ability and distinc- 

 tion till his death on Monday, the 3rd of the present 

 month. 



His first contribution to science was a paper on a 

 chemical subject in 1842, this being a science of which 

 he was Lector at the time ; but soon thereafter he turned 

 his attention to meteorology, which he emphatically made 

 the business of his life. The following are among the 

 earlier of his papers on the subject, and they are, it will 

 be seen, very significant of his future work : — " On the 

 Influence of the Rotation of the Sun on the Temperature 

 of our Atmosphere," in 1846; "On the Importance in 

 Meteorology of Deviations from the Mean States of the 

 Atmosphere," in 1850; "Results of the Observations of 

 1849 and 1850 in different places in Holland," in 1851 ; 

 and " On Synchronous Representations of Weather 

 Phenomena," in 1854. 



In these early times of meteorology, when instruments 

 and modes of observing still greatly needed the guiding 

 hand of science towards the founding of international 

 meteorology. Dr. Buys Ballot was wisely led to attempt 

 the construction of no general isobaric and isothermal 

 maps in investigating storms and other weather pheno- 

 mena, but contented himself in investigating weather dis- 

 turbances by representing them over the surface of Europe 

 by means of deviations from the means, or averages, of the 

 places represented. In this mode of working he made 

 several of his more important contributions to meteoro- 

 logy, and out of it developed the system of storm warnings 

 he issued for Holland. In this connection his barometric 

 and thermometric means for a very large number of places 

 over Europe will long be a standard work. Of these contri- 

 butions, unquestionably the most important is that known 

 as Buys Ballot's Law of the Winds, which states the 

 relation between the direction of the wind and the distri- 

 bution of atmospheric pressure at the time the wind is 

 blowing. This relation was further developed by Dr. 

 Buchan in 1869, in his paper on the mean pressure of the 

 atmosphere and prevailing winds of the globe, in which 

 it was shown that the prevailing winds of all climates are 

 simply the result of the distribution of pressure. 



One of the most exhaustive discussions of the influence 

 of the moon on weather was made by Dr. Ballot. The 

 discussion covered a period of about a century, and he 

 showed that the longer the period the closer do the cases 

 for or against any such influence approach equality. Sub- 

 sequent to Maury, Dr. Ballot was one of the earlier and 

 most energetic and successful workers in maritime me- 

 teorology, and his meteorological charts of the routes of 



Dutch ships over the great oceans is a standard work. 

 Dr. Ballot also took an active and efficient part in the 

 Meteorological Conferences and Congresses held at in- 

 tervals from 1872 to 1888, which have brought about a 

 greater uniformity in meteorological observations and 

 discussions than previously existed. He was chosen, by 

 the first Congress, President of the Permanent Commit- 

 tee. Among his last works was the proposal of a method 

 of developing and representing the variability of the 

 weather and climates by the values of the deviations of 

 the daily observations from the averages, irrespective of 

 sign. 



The great merits of his indefatigable services to science, 

 but more particularly to meteorology, were recognized by 

 his being made LL.D. of Edinburgh University, Knight of 

 the Order of the Netherland Lion,Commander of the Order 

 of Franz Joseph of Austria, and of S\ James of the Sword 

 of Portugal, and Knight of second class of the Prussian 

 Order of the Crown. But above all, his ever readiness 

 in every degree to obhge, the genial sunshine of his face, 

 and his lovableness, make his death to be felt by many of 

 us as a sharp personal bereavement. 



NOTES. 



On Tuesday evening the Cambridge University Natural 

 Science Club and the Master of Downing (Dr. Alex. Hill) gave 

 a conversazione at Downing Lodge, at which 260 guests, in- 

 cluding many distinguished residents and non-residents, were 

 present. The several scientific professors were very liberal in 

 lending the treasures from their museums, and as this is the first 

 entertainment of the kind which has been given in Cambridge, 

 many objects • of great historic interest, such as Babbage's 

 calculating machine, Cavendish's apparatus, &c., were exhibited. 

 Artificial silk was spun, quartz filaments drawn, smokeless gun- 

 powder and other scientific novelties shown. One of the most in- 

 teresting exhibits was a series of Egyptian heads unwrapped from 

 their mummy cloths, and artfully "restored" by Prof. Macalister. 

 A very attractive feature of the entertainment was an address by 

 Dr. Lauder Brunton, who had much that was interesting to say 

 about his recent experiences in India. Mr. Gardiner illustrated 

 the dispersion of seeds by the aid of the limelight and boxes 

 of seeds of various kinds suspended from the ceiling. 



The annual general meeting of the Geological Society of 

 London will be held to-morrow (Friday) at 3 o'clock, and the 

 Fellows and their friends will dine together at the Criterion 

 Restaurant at 7.30 p.m. 



Before the next ordinary meeting of the Royal Microscopical 

 Society, it will have moved its quarters from the rooms hitherto 

 occcupied by it in King's College, which are now required for 

 the purposes of the College, to 20 Hanover Square. The 

 ordinary meetings will in future be held on the third instead of 

 the second Wednesday in the month, and the annual meeting 

 in January instead of February. The Quekett Microscopical 

 Club has also transferred its place of meeting to 20 Hanover 

 Square since the commencement of the year. 



We regret to have to record the death of Sir Robert Kane, 

 F.R.S. He died after a short illness on Sunday, the i6thinst., 

 at his residence in Dublin. 



The fine buildings of the University of Toronto were almost 

 wholly destroyed by fire last Friday. The flames were un- 

 fortunately fanned by a strong wind, and the fire spread so 

 rapidly that hardly anything could be saved. A small number 

 of specimens in the museum, and some of the scientific apparatus, 

 were brought out by students, but they were mostly broken while 



