Proft'ssor WhczocWs Address. 431 



by the presidents and vice-presidents. Thereafter, Professor 

 Powell delivered a highly interesting lecture on the undulatory 

 theory of light. Professor Whewell was then requested to state 

 the results of the late tidal ubscrvafmis. 



The general opinions and facts referred to by the Professor may be 

 collected from his papers read at the Royal Society. In conclusion, how- 

 ever, he observed, — " It was a curious circumstance, that when the atten- 

 tion of the scientific world had been first turned to the tides, observations 

 had been simultaneously begun under the direction of the Royal Society of 

 London, and of tlie Paris Academy of Sciences. These observations had 

 been continued for some time, until, finding either the problem too diflicult, 

 or the perseverance too tiresome, the observers had almost all abandoned 

 their undertaking, without furnishing sufficient data for arriving at a final 

 and valuable result. There were two objects of inquiry with regard to 

 tides ; first, the laws of their relation to time j and, secondlj', to space. 

 Attempts had been made to ascertain the rate at which the tide travel- 

 led, but as yet they had been ineffectual. In June 1834, observations had 

 been ordered to be made by the coast-guard along the coasts of Great 

 Britain and Ireland : returns had thus been procured from 500 difierent 

 stations. The reduction of these had been only partially effected. In 

 the paper which he held in his hand, he had drawn up liis conclusions 

 from these observations. They had done this much, that they had thrown 

 great light on the circumstances attending the meeting, of the two tides — 

 the one which ran up the British Channel, the other (we believe) from 

 the Northern Ocean. This was a subject of inquiry equally interesting 

 to the man of science and the navigator. In June 1835, fresh orders 

 ■were issued to continue these observations along the same extent of Bri- 

 tish coast, and application for assistance had been made through the 

 ministers of foreign powers. In every case they had been cordially met, 

 and there was not a maritime state in Europe, not one north of theequa- 

 tor, that was not contributing its assistance to this great work : Sweden, 

 Denmark, Russia, Spain, France, Holland, and the United States, had all 

 joined in it. He could not but express his gratitude for the labours of 

 one foreigner, who was now present, he meant Professor Moll of Utrecht, 

 who had furnished them with many valuable returns from the coast of 

 Holland — returns procured by much personal exertion. Monotonous, 

 and calm, and tranquil, as the life of a man of science might appear, his 

 inquiries were sometimes agreeably diversified by an incident of danger. 

 The boat in which the Professor used to make his observations had been 

 on one occasion swamped by the tide which he was examining ; fortu- 

 nately, for the interests of science, the crew were saved. By tlie next 

 meeting of the British Association he hoped that the inquiries commen- 

 ced under these favourable auspices will have led to some favourable re- 

 sults. He begged the meeting to bear in mind the general law which 

 he had stated of the progress of knowledge ; from arts to phenomena — 

 from phenomena to laws — from laws to causation. It might, it was true, 

 be said, that the cause of the tides was already known to be the attrac- 

 tive influence of tlie moon ; but then, this had been ascertained not by 

 the observation of the tides ; these influences had been discovered in in- 

 quiries of another character, and in the investigation of phenomena, even 

 in point of space, far remote from the tides on this world, and, so dis- 

 covered, had been applied to the solution of the phenomena of tides. 

 But he would go further, and say tliat no one would, even now, be hardy 

 enough to hazard the assertion, if it rested on the unsupported evidence 

 of the tides themselves. We knew, indeed, generally, that these influ- 



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