19.2 report — 18G5. 



Interim Report of the Committee on the Transmission of Sound under 

 Water, consisting of the Rev. Dr. Robinson, Prof. Wheatstone, 

 Dr. Gladstone, and Prof. Hennessy. 



When the Committee on. Fog-signals stated at the Meeting of the British 

 Association last year that no success had attended their efforts to induce the 

 Board of Trade to undertake experiments on the subject, it was thought 

 advisable to change the mode of procedure. The Parliamentary Committee 

 was requested to press on the Government the expediency of instituting such 

 experiments, while the Committee was reappointed for the purpose of making 

 experiments on the transmission of sound under waer — a line of inquiry 

 suggested by us in our memorial to the President of the Board of Trade, 

 June 18, 1803. The sum of =£30 was placed at our disposal, and to this the 

 Government-Grant Committee of the Royal Society have added £100. 



The subject of the production of sound under water, and its transmission 

 through that medium, had previously engaged the attention of one of our 

 number, Professor Wheatstone, and we naturally wished to be guided in our 

 first trials by his experience. A long and serious illness unfortunately 

 delayed the commencement of that gentleman's experiments ; but the inves- 

 tigation has been fairly begun this summer. The results hitherto arrived 

 at are instructive and promising, but they are not sufficiently precise to 

 warrant their publication. We have therefore only to report progress, and 

 to ask the British Association to give us the opportunity of bringing our 

 results before them next year. 



On the Rainfall of the British Isles. By Gr. J. Symons, M.B.M.S. 



In my previous reports on the progress of rainfall-investigations I have 

 scarcely referred to what had been done before I undertook the collection and 

 organization to which 1 have now devoted nearly six years. 



I purpose to supply the omission on this present occasion, and to divide my 

 Report into the following divisions :■ — ■ 



1. What had been done prior to 1860. 



2. What has been done since 1860. 



3. What remains to be done. 



4. A few particulars respecting the rainfall of the last fifty years, and 



the fall in 1864. 

 1. What had been done prior to 1860. — Raving been almost wholly en- 

 gaged during the past year in clearing up arrears, and in thoroughly classifying 

 the materials hitherto collected, the imperative necessity of circulating 

 amongst engineers, meteorologists, and rainfall-observers a complete index of 

 the collected observations has been brought prominently before me. I have 

 therefore prepared such an index, and annexed it to this lleport. Besides its 

 general usefulness, it will be specially so in. two respects. (1) Every station, 

 whether discontinued or not, being entered, with the years between which 

 observations have been obtained, and with observer's name, and height above 

 sea-level, any one, whether engineer, agriculturist, or physicist, can ascer- 

 tain with the greatest ease exactly what observations have hitherto been col- 

 lected. In order to facilitate reference, the stations are arranged alphabetically 

 in counties; and there are also provided general indexes of England and 



