462 REPORT — 1856. 



stand of clay, which being at first soft, giadually hardened and became a firm 

 support to the object. The cement employed was liquid glue, i. e. shell-lac 

 dissolved in naphtha. 



Interim Report to the British Association on Progress in Researches 

 on the Measurement of Water by Weir Boards. By James 

 Thomson, C.E. 



Belfast, August 6, 1856. 

 Having at last year's meeting of the Association read in the Mechanical 

 Section a short paper on the Measurement of Water by Weir Boards, and 

 having been requested by the General Committee to prepare a Report on 

 the same subject, 1 beg now to state that I have in the mean time been 

 collecting information for the purposes of that Report. My professional 

 engagements have occupied me necessarily so much as to oblige me to defer 

 for this year the detailed prosecution of the subject and the preparation of 

 the Report in full. 1 have, however, the gratification of stating, that, with 

 special reference to the researches entrusted to me by the Association, the 

 President of the Athenaeum of Boston, United States, Mr. Thomas G. Gary, 

 has generously sent to me, with the request that it be presented to the 

 British Association on his behalf, a valuable book containing accounts of 

 experiments recently carried out on a very grand scale in America, on the 

 measurement of large bodies of flowing water by means of weir boards and 

 by other methods, and on the performance of Turbine Water Wheels. 



The work is entitled "Lowell Hydraulic Experiments," by James B. Francis. 

 In reference to the experiments, Mr. Gary, the donor of the book, states in 

 his letter to me, — " These experiments, made under the direction and at the 

 expense of the Associated Gompanies of Lowell near Boston, who employ 

 Mr. Francis as the engineer for their cotton and woollen factories, have cost 

 about fiOOO sterling; and they make part in a series of investigations which 

 have cost those Gompanies £15,000." 



In the Report which I hope to submit to the British Association, I shall 

 have much occasion for reference to these important experiments, and, for 

 this purpose, I think it right to retain the book in m^ hands at present. 



As the expenses incurred in reference to the researches have been but 

 small, and chiefly for the procuring of books, I do not desire to draw, for 

 them, on the fund of £10 placed at my disposal by the Association ; and as 

 my intention is not to conduct experiments on the subject myself, but chiefly 

 to give a review of the most important experiments and deductions which 

 have been made by others, I do not think it necessary to ask for a renewal 

 of the grant. James Thomson. 



On Observations with the Seismometer. By R. Mallet, C.E., 

 M.R.LA. 



A Provisional Report was presented. The author is continuing his re- 

 searches at Holyhead. 



On the Progress of Theoretical Dynamics. By A. Caylev, M.A., 



F.R.S. 



A Provisional Report was presented. The author proposed to deliver in 

 the complete Report in 1857. _^_____ 



