112 British Association, 



Mr. Baily congratulated Dr. Robinson on the successful termina- 

 tion of his labours. He stated, that it was a curious fact, that Busch, 

 of Berlin, had, from a series of observations made by Bradley at Wan- 

 stead, before he removed to Greenwich, computed the nutation, and 

 given its value 9"'2347, thus differing by only 7 ten-thousands of a 

 second from the value deduced by Dr. Robinson, although the cycle 

 of observations was different, the instruments and places of observa- 

 tions and the observers were all different : this was a coincidence 

 scarcely to be equalled in the annals of science. — Sir William Hamil- 

 ton asked some questions regarding the manner in which the obser- 

 vations of the pole-star were used by Dr. Robinson as contrasted 

 with the method adopted by Lindenau, and seemed satisfied with the 

 answers which were given. He stated, that he felt great gratification 

 at what he might almost call the complete solution of this important 

 problem, and expressed his concurrence in the conclusion to which 

 Dr. Robinson had come in consequence of the discrepancies between 

 the calculated declinations and those given in the Nautical Al- 

 manac. 



Mr. Russell then presented the Report of the Committee on Waves. 

 — Mr. Robison and Mr. Russell, of Edinburgh, had been appointed 

 at the Bristol Meeting of the British Association a Committee to 

 prosecute an inquiry concerning the Mechanism of Waves, in which 

 Mr. Russell had been previously engaged, and to extend their obser- 

 vations to the determination of the effect of the form of channel and 

 of the wind upon the tidal wave. Mr. Lubbock and Mr. Whewell 

 had already determined by their investigations the laws of the propa- 

 gation of the oceanic tide, but it still remained to assign the law of 

 propagation of the tide in those shallow seas and rivers where the 

 bottom and sides of the channel exercise the principal influence on 

 the propagation of the tidal wave. For the purpose of determining 

 the effect of these circumstances upon the form, magnitude, and ve- 

 locity of the tide wave, Mr. Russell had made in September, 1836, 

 a series of observations on the River Dee, below Chester, where that 

 river has a form and dimensions admirably suited to the purpose. It 

 appears that for more than five miles in length the banks of the Dee 

 are perfectly straight, quite parallel to one another, while the depth 

 of the channel at low water is nearly uniform throughout the whole 

 of that length. Now, in this river there is a tidal wave of from six to 

 fifteen feet, forming, in fact, a tidal canal of large dimensions. On 

 this part of the river the first series of observations was made. A 

 second series of observations was made upon the River Clyde in April 

 and May, 1837, under peculiar advantages. On the application of 

 Sir Thomas Brisbane, a former President of the Association, the 

 Trustees of the River Clyde offered to Mr. Russell all the assistance 

 at their disposal, and every facility for making observations, which 

 they conceived to be equally useful to practical navigation as to the 

 advancement of abstract science j and their engineer, Mr. Logan 

 had contributed much to the success of these observations. Accurate 

 trigonometrical surveys of the channel of the river, with correct levels 

 and transverse sections, were obtained, and a series of simultaneous 



