Mathematkal and Physical Science. 321 



form, for which Mr Lubbock satisfactorily accounted, by stating, 

 that tlie observations were neither sufficiently numerous,' nor suf- 

 ficiently precise, from the very manner in which they were taken 

 and recorded, to warrant «in expectation of a closer conformity, 

 or a more regular curvature. When it is recollected that the 

 observations are at first written on a slate, and then transferred to 

 the written register, by men otherwise much employed, and whose 

 rank in life was not such as would lead us to expect scrupulous 

 care, it was not to be wondered at, if occasionally an error of tran- 

 script should occur, or even if the observation of one transit was 

 set down as belonging to the next. When to these circumstances 

 it was added, that the tide at London was in all probability, if not 

 certainly, made up of two tides, one having already come round the 

 British Islands, meeting the other as it came up the British Channel, 

 it was altogether surprising that the coincidence should be so ex- 

 act ; and it was one among many other valuable results of thei^e 

 investigations, that it was now pretty certain, that tide tables con- 

 structed for the port of London by the theory of Bernouilli, would 

 give the height find interval with a precision quite sufficient for all 

 practical purposes, .nnd which might be relied on as sufficiently ex- 

 act, when due caution was used in their construction, and the ne- 

 cessary and known corrections applied. In conclusion, Mr Lub- 

 bock stated that the observations for the port of London had now 

 been continued from the commencement of this century, and those for 

 Liverpool, as we understood, about twenty-five years. 



8. Mr Whewell gave an account of the proceedings of the com- 

 mittee appointed to fix lines of the relative level of sea and land. 

 He commenced by saying, that as in the discussion of the relative 

 level of land and sea, the tides of the ocean were an important ele- 

 ment, he should preface the remarks upon that subject, which he 

 intended to submit, by making a few observations upon the very 

 valuable communication of his friend Mr Lubbock. This com- 

 munication he highly eulogized, and pointed out to the Section the 

 importance of many of the conclusions, should they prove hereafter 

 to be generally applicable : but he expressed strongly his fears that 

 this would not be the case. Observation had, in the instance of 

 the tides, far outstripped theory, for many reasons, which it would 

 be impossible to detail ; but among the most prominent were the 

 complexity of the problem itself involving the astronomical theories 

 both of the sun and moon ; the masses of these bodies ; the mo- 

 tions of disturbed fluids, and local causes tending to alter or modify 



