264 report— 1865. 



Report of the Gun-cotton Committee, consisting of William Fair- 

 bairn, LL.D., F.R.S., Joseph Whitworth, LL.D., F.R.S., James 

 Nasmyth, C.E., F.R.A.S., J. Scott Russell, C.E., F.R.S., John 

 Anderson, C.E., Sir William G. Armstrong, C.B., LL.D., F.R.S., 

 Dr. Gladstone, F.R.S., Prof. W. A. Miller, M.D., F.R.S., Prof. 

 Frankland, F.R.S., and F. A. Abel, F.R.S. 



After the report presented by this Committee at the Newcastle Meeting 

 two years ago, the British Association, through a deputation headed by 

 General Sabine, drew the attention of the Minister for War to the probable 

 usefulness of Gun-cotton. In January 1864, the Government appointed a 

 Committee to investigate the subject in all its bearings. This Committee 

 consists of General Sabine as President, General Hay, Captain Brandreth, 

 B.N., Commander Liddell, B.N., Colonel Boxer, E.A.., Colonel Lovell, R.E., 

 F. A. Abel, Esq., T. Sopwith, Esq., Professor W. A. Miller, Professor G. G. 

 Stokes, and Dr. J. H. Gladstone, with Major Miller, R.A., as Secretary; 

 representing thus the army, the navy, military and civil engineering, as well 

 as chemical and physical science, and comprising three of the members of 

 the British Association Gun-cotton Committee. Experiments on an exten- 

 sive scale, and in a systematic manner, have been carried on by this Govern- 

 ment Committee, and are still in progress ; but no report has yet been published. 

 Until that report is made, your Committee have suspended their labours. 



On the Horary and Diurnal Variations in the Direction and Motion 

 of the Air at Wrottesley , Liverpool, and Birmingham. By A. 

 Follett Osler, F.R.S. 



[A communication ordered to be printed among the Reports.] 



Anemometkical observations having been taken hourly with considerable 

 accuracy for several years, and those at Wrottesley, Liverpool, and Bir- 

 mingham having been recorded on exactly the same principle (originally 

 commenced by Mr. Hartnup in 1852), I was desirous of tabulating the 

 results from those stations on a plan which I thought might prove of some 

 value in extending our knowledge of the motion of the air in these latitudes, 

 and possibly of developing some further laws bearing on that subject. 

 Having observed that the hourly records of certain currents obtained from 

 the integrating anemometer seemed to exhibit some peculiar features different 

 from those I had obtained from the registration of the force of the wind, I 

 wished, in the first place, to carry out some investigations on the horary 

 variations by taking out the amount of horizontal motion instead of the 

 force ; the records of Dr. Kobinson's integrating instrument have therefore 

 been arranged in conjunction with those of time and direction, these 

 registers being peculiarly suited for accurate tabulation, much more so than 

 those of the force, which are most available for examining storms and sudden 

 changes and marked variations in the aerial currents. 



Besides these hourly results, I desired to investigate the records of the 

 daily variations in the atmospheric currents throughout the year, with a view 

 of ascertaining whether indications of any laws could be detected respecting 

 their periodicity and amount. 



Accordingly I applied to Lord Wrottesley, who most kindly placed the 

 whole of the valuable anemometrical records taken at his observatory at my 



