266 Pi'oceedings of the British Association 



of those observations. I have the gratification of stating that consid- 

 erable progress has now been made in preparing them for the press. 



At the lust meeting of the Association, a project was laid before the 

 General Committee, by M. Kupffer, for the formation of a Meteoro- 

 logical Confederation, to be extended over the whole of Europe. A 

 very extensive organization, covering almost the whole Russian Em- 

 pire, has already been created. The Council to whom the project was 

 referred, after very careful consideration, deemed it inexpedient to jcin 

 in the proposed Confederation. They were deterred by various prac- 

 tical difficulties, of which some may perhaps always exist, while others 

 are felt with unusual force at the present time. It was with extreme 

 unwillingness that the Council adopted this resolution, and with the full 

 hope that at some future time a confederation similar to that proposed 

 by M. Kupffer may be firmly established. 



Under the auspices of the Board of Ordnance, the officers of the 

 corps of Koyal Engineers are making arrangements for the establish- 

 ment of a uniform system of meteorological observations, of a simple 

 kind, at the principal engineers' stations in every pari of the earth. If 

 with these could be combined occasional trustworthy observations at 

 sea, we should probably have the most complete system of Terrestrial 

 Meteorology that we can hope to obtain. 



Among the systematic observations of less ostentatious character, I 

 cannot omit referring to the daily report of the state of the wind at 9 

 o'*clock every morning, which is supplied by the superintendents of 

 railway stations, over a great portion of the British isles, and printed in 

 the Daily Neios newspaper. 



A new Meteorological Society has been formed, which (I believe) is 

 at least in this respect, superior to those which have preceded it — that 

 the instruments used by the various amateur members are strictly com- 

 parable : great attention having been given to the adjustments of the 

 instruments, by the Secretary, Mr. Glaisher. 



In Optics, two or three investigations of rather important character 

 have, since the last meeting of the Association, attracted public atten- 

 tion. Experimental measures of the velocity of light in air and in 

 water, made by MM. Foucault, Fizeau and Brequet, with apparatus 

 nearly similar to that employed long ago for analogous purposes by 

 Mr. Wheatstonc, appear to leave no doubt that the velocity in water is 

 less than that in air, — a most important, and indeed critical, result in 

 regard to theories of light. A remarkable investigation by Prof Stokes, 

 when compared with experiment, seems to establish that the vibrations 

 constituting polarized light are, as for other reasons was supposed by 

 Fresnel, perpendicular to what is usually called the plane of polariza- 

 tion. Some optical theories which admitted formerly of very imper- 

 fect mathematical treatment have been brought under the dominion of 

 analysis by Prof. Stokes's powerful methods of investigation- A curi- 

 ous series of experiments on diffraction has been published by Lord 

 Brougham ; but they have at present no bearing on theory, as the 

 theoretical calculations with which they must be confronted appear to 

 be too difficult or too complicated for the present state of pure mathe- 

 matics. The experiments of Jamin regarding the reflection of polar- 

 ized light under peculiar circumstances appear to give support to the 



