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V. On the Results of Tide Observations made in June 1834 at the Coast Guard Sta- 

 tions in Great Britain and Ireland. By the Rev. William Whewell, F.R.S., 

 Fellow of Trinity College, Cambridge. 



Received March 27, — Read April 2, 1835. 



In the conclusion of " An Essay towards a first Approximation to a Map of Cotidal 

 Lines/' published in the Philosophical Transactions for 1833, I stated my opinion that 

 simultaneous tide observations, made at the stations of the Preventive Service, and 

 continued for a fortnight, would give us a clearer view of the progress of the tide 

 along the coasts of this country than we could acquire from any records then extant. 

 A representation to this effect being made to Captain Bowles, the Chief Commis- 

 sioner of that Service, and to Captain Beaufort, the Hydrographer of the Admiralty, 

 those gentlemen entered with great interest and activity into the proposal for pro- 

 moting this branch of science by such a series of observations ; and they undertook 

 to give orders for carrying the plan into effect, and directions for its execution. Such 

 observations were accordingly made at all the Preventive Service stations on the 

 coasts of England, Ireland, and Scotland, from June 7 to June 22 inclusive, and the 

 registers of the observations were sent to the Admiralty, where they now are. 



I expected to be able to deduce from these returns the solution of several curious 

 and important questions respecting the tides, and probably to obtain some new laws 

 of their phenomena. For this purpose, however, it was necessary to perform a pre- 

 vious reduction of the registered observations, correcting the times as far as the 

 methods employed would allow, and subtracting from each time of tide the time of 

 the previous transit of the moon, in order to obtain the interval. Though this opera- 

 tion was very simple, the performance of it in so many cases (above 12,000) required 

 more time than I could devote to it. Captain Beaufort kindly allowed it to be exe- 

 cuted by Mr. Dessiou, of the Hydrographer's Office ; and it was my intention to defer 

 laying the account of the observations before the Society till the whole of them had 

 been reduced, and their results investigated. But Mr. Dessiou, having executed this 

 reduction for the whole of the south coast of England, has been prevented by illness 

 and by more pressing employments, from proceeding to the remaining coasts. In 

 the mean time, having examined the reduced observations, I have been led to some 

 conclusions which appear to me interesting and important ; and which, I think, con- 

 sidering the delay which may attend the reduction of the remaining returns, and the 

 intention which is entertained of repeating the observations in the ensuing June, it 

 may be worth while very briefly to announce. I shall defer the communication of 



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