Page:Proceedings of the Royal Society of London Vol 4.djvu/25

Rh 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 immediame 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 mark, 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 remarks on the pro— priety of the position of the several meteorological ins ruments of the Society. With respect to the barometer, he says he is not aware that any objection can be offered; and as to the hygrometer, the ob— servations have been found, by recent trials, not to differ 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 he wished, but is the [lest the house affords.”

November 23, 1837. FRANCIS BAILY, Esq, VP, 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 Daniel], Esq. ; Sir Philip Grey Egcrton, Bart. ', Davies Gilbert, Esq. ; and Stephen Peter Rig-and, Esq.

Frederick William Mullins, Esq, was balloted for, but not elected into the Society.

“ Magnetical Observations made in the l-Vest Indies, on the Coasts n 2