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the old barometer, prior to 1823, was fixed up in the Council-room 

 of the Society, or the contiguous ante-room : but when Mr. Daniel's 

 barometer was finished, at the end of the year 1822, it was fixed up 

 in the closet adjoining the library, on the floor which is immediately 

 over the Council-room ; the assumed difference in the elevation of 

 the two floors (namely, 19 feet) having since been ascertained to be 

 correct. 



With respect to the new reference of altitude, namely, the fixed 

 mark at Waterloo Bridge, much doubt has frequently been expressed 

 about its existence, since no person had been able to discover it. 

 The fact is that there is no mai^k, in the common acceptation of the 

 term ; but the intended reference is nevertheless more conspicuous, 

 more durable, and more convenient than any mark that could have 

 been inscribed by hands. This standard mark, or level, was fixed 

 on by Mr. Bevan in the year 1827, at the request of the Council of 

 this Society : and it is the surface of the granite pedestal at the 

 base of the columns, at the north abutment of the bridge, and on the 

 eastern side ; which is about 5 feet above the lowest platform, or 

 landing, at the stairs. Nothing therefore was wanting but the dif- 

 ference of level between this mark and the one made by Capt. Lloyd 

 at London Bridge, the height of which above the mean level of the 

 sea had been determined by him. This has been recently done by 

 Sir John Rennie, at the request also of the Council : and the result 

 of the whole is, that the cistern of the barometer is 97 feet above the 

 mean level of the sea. 



The author concludes his paper with some rem.arks on the pro- 

 priety of the position of the several meteorological instruments of 

 the Society. With respect to the barometer, he sa3^s he is not aware 

 that any objection can be off'ered ; and as to the hygrometer, the ob- 

 servations have been found, by recent trials, not to diff'er materially 

 from some expressly made in another position, at King's College, 

 which was considered to be more favourable for such experiments. 

 It therefore only remains to speak of the external thermometer and 

 of the rain-gauge ; of which all that can be said on the subject would 

 be merely a repetition of what was justly said sixty years ago by Mr. 

 Cavendish on a similar occasion (Philosophical Transactions, 1776), 

 namely^ " that, on the whole, the situation is not altogether such as 

 could be vdshed, but is the hest the house afl'ords." 



November 23, 1837. 

 FRANCIS BAILY, Esq., V. P. and Treasurer, in the Chair. 



The following gentlemen were, by ballot, elected Auditors of the 

 Treasurer's accounts, on the part of the Society, viz. John Frederick 

 Daniell, Esq. ; Sir Philip Grey Egerton, Bart, ; Da\des Gilbert, Esq. ; 

 and Stephen Peter Rigeud, Esq. 



Frederick WiUiam Mallins, Esq., was balloted for, but not elected 

 into the Society. 



" Magnetical Observations made in th© West Indies, on the Coasts 



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