Proceedings of the British Association. 373 



Dr. Thomson read a very valuable paper on mixtures of sulphuric 

 acid and water, in which he shewed that the theory of Irvine re- 

 specting specific heat cannot be true. 



Mr. Jones detailed the results of an elaborate analysis of wheat 

 and mentioned that he had formed a new and peculiar volatile fluid 

 by the action of sulphuric acid on wheat. 



Section C. — Geology and Geography. 



A paper was read by the IMarquis Spineto on the geographical 

 position of Memphis, in Egypt. The state of that city during the 

 time of its long prosperity was first considered ; then the causes of 

 its destruction ; and lastly, the opinions of different travellers re- 

 garding its position. Its particular site had been described by an- 

 cient historians as on an island in the Nile, evidently formed of the 

 mud of that river ; and that it had been protected from inundations 

 by various extensive works erected by its kings. When its splen- 

 dor decayed, these works went oiit of repair, and hastened the ruin 

 of the city, which strewed with its fragments tlie place on which it 

 had stood. Finally, it was submerged under drifted sand, and its 

 true position became a problem to modern travellers. Of late, how- 

 ever, the site has been determined by the French, who, in one of 

 their exploring expeditions, had examined the stratification of the 

 place supposed to be Memphis, and they ascertained the spot by the 

 succession of drifted sand, ruins, and mud. Its latitude they fixed 

 at 29° 20' N. and longitude at 31° 30' E. from Greenwich.— Mr. 

 Murchison spoke of the great value of geographical papers to the 

 geologist, and of the one just read, as an excellent example of this 

 kind. — Dr. Buckland took this opportunity of mentioning the estab- 

 lishment of M. Van derMaelen, at Brussels. That gentleman had 

 devoted, in the most praiseworthy manner, his time and fortune to 

 the advancement of science, by making large geographical and geo- 

 logical collections, for the purpose of diffusion over the world, by 

 means of exchange with societies or individuals. Dr. Buckland ad- 

 vocated such a mode of obtaining maps and specimens to the differ- 

 ent provincial societies of the United Kingdom. 



The next paper was on the change in the chemical character of 

 minerals induced by galvanism. Mr. Fox mentioned the fact, long 

 known to miners, of metalliferous veins intersecting different rocks, 

 containing ore in some of these rocks, and being nearly barren or 

 entirely so in others. This circumstance suggested the idea of some 



