TRANSACTIONS OF THE SECTIONS. 11 



the train. The direction of the train, towards or from the sun, is, according to this 

 theory, to be easily explained by the supposition of a variability in the mutual elec- 

 trical conditions. This accords perfectly with the phenomena observed in the 

 development of electricity by vapour-streams in the hydroelectric machine, where 

 the sign of the electricity depends upon the presence or absence of various sub- 

 stances in the boiler or the tubes. 



The theory acquires an additional interest fi'om Schiaparelli's remarkable dis- 

 covery of the identity of the paths of certain comets witli great meteor-streams, 

 since the meteoric masses must inevitably be converted into vapour on approaching 

 the sun, with exhibition of the characteristic appearances of the comets. 



The intimate connexion of planetary configuration and solar spots, of the latter and 

 teiTestrial magnetism and auroral phenomena, must tend to establish also a connexion 

 between solar spots and solar radiation. It is demonstrated, by the researches of 

 Piazzi Smyth, Stone, and Cleveland Abbe, that there is a connexion between the 

 amoimt of heat received from the sun and the prevalence of spots — a result clearly 

 in harmony -Rath those derived from recent investigations into the nature of the solar 

 atmosphere. Further, in a paper by Mr. Meldrum, of Mauritius, which will be read 

 before you during this session, most remarkable evidence is given on the close con- 

 nexion of these phenomena. It appears that the cyclones of the Indian Ocean have 

 a periodicity corresponding with the sun-spot periodicity ; so that if an observer in 

 another planet could see and measure the sun-spots and cyclones (earth-spots), he 

 would find a close harmony between them. Such a connexion will probably be 

 found to exist over the globe generally ; but with reference to the Indian Ocean it 

 may be stated as a matter of fact, from Mr. Meldrum 's discussion of twenty-five 

 years' observations, that in the area lying between the equator and 25° south lati- 

 tude, and between 40° and 110° east longitude, the frequency of cyclones has varied 

 during that period directly as the amount of sun-spots. I am glad to be able to 

 announce that Mr. Meldrum, in order to place the deductions on a still broader foun- 

 dation, proposes to investigate these laws on a plan perfectly in agreement with our 

 method of determining the areas of solar disturbances, the results of which have been 

 published from time to time during the last ten years. Moreover the observations 

 on the periodic changes of Jupiter's appearance, and the observations of Mr. Bax- 

 endell that the convection-currents of our earth vary according to the sun-spot period 

 — all these results, seemingly solitary, but truly in mysterious harmony, point to 

 the absolute necessity for establishing constant photographic records of solar and 

 terrestrial phenomena all over the world. No astronomer or physicist should lose 

 any opportunity of assisting in this great aim, by which alone unbiased truthful 

 records of phenomena can be preserved. What is more, no system of observations 

 can be carried on at a less expense. 



_We have hopes of seeing the photographic method as applied to sun-observations 

 joined to the work of the Greenwich Observatory ; but what is further wanted is the 

 erection of instruments for photogi-aphic records and of spectroscopes in a number 

 ^^ of obsei-vatories throughout the world, so as to obtain daily records of the sun and 

 to observe magnetical and meteorological phenomena continuously in connexion 

 with solar activity. Meteorological observation is storing up iiseful facts ; but 

 they can only be dealt with effectually if investigated in close parallelism with 

 other cusmical phenomena. Only when this is done may we hope to penetrate 

 the maze of local meteorological phenomena and elevate meteorology to the rank 

 of a science. The time has really come not only for relieving private observers 

 from the systematic observation of solar phenomena, but for drawing close ties 

 between all scattered scientific observations, so as to let one grand scheme embrace 

 the whole ; and no method seems to be so well adapted to bring about this great 

 achievement than the method of photographing the phenomena of nature, which 

 in its very principle carries with it all extinction of individual bias. 



In conclusion I cannot refrain from making a passing allusion to a Royal Com- 

 mission, presided over by the Duke of Devonshire, which has been sitting for some 

 time past ; for I believe that its labours will have an important bearing on all that 

 relates to scientific education and the promotion of science in this countiy. The 

 time has come when the cultivation of science must be protected and fostered by 

 the state ; it can no longer be safely left to individual efforts. If England is to 



