126 Observations on Sculptured Marks on 



by requiring a much smaller mass of fluid to give the same 

 length of a degree : this I propose to test by making a ther- 

 mometer with the same size of tube and bulb as those to be 

 experimented on with mercury. In mentioning these experi- 

 ments to Professor Forbes, he kindly put me in possession of 

 some spirit-thermometers, one of these, made in 1837, having 

 a very large bulb — this, with three others, shewed no change 

 in the places of their freezing points. 



Observations on the Discovery, by Professor Lepsius, of Sculp- 

 tured Marks on Bocks in the Nile Valley in Nubia; indicat- 

 ing that, within the historical period, the river had flowed at 

 a higher level than has been known in Modern Times. By 

 Leonard Horner, Esq., F.R.S.S. L. & E., F.G.S., &c. 

 Communicated by the Author. With a Plate. 



The recent archaiologcal researches of Professor Lepsius in Egypt, 

 and the Valley of the Nile, in Nubia, have given a deserved celebrity 

 and authority to his name, among all vtho take an interest in the 

 early history of that remarkable portion of the Old World. While 

 examining the ruins of a fortress, and of two temples of high antiquity 

 at Semne, in Nubia, he discovered marks cut in the solid rocks, and 

 in the foundation-stones of the fortress, indicating that, at a very re- 

 mote period in the annals of the country, the Nile must have flowed 

 at a level considerably above the highest point which it has ever 

 reached during the greatest inundations in modern times. This re- 

 markable fact would possess much geological interest with respect 

 to any great river, but it does so especially in the case of the Nile, 

 Its annual inundations, and the uniformity in the periods of its rise 

 and fall, have been recorded with considerable accuracy for many 

 centuries ; the solid matter, held in suspension in its waters, slowly 

 deposited on the land overflowed, has been productive of changes in 

 the configuration of the country, not only in times long antecedent 

 to history, but throughout all history, down to the present day. Of 

 no other river on the earth's surface do we possess such or similar 

 records ; and moreover, the Nile, and the changes it has produced 

 on the physical character of Egypt, are intimately associated with 

 the earliest records and traditions of the human race. Everything, 

 therefore, relating to the physical history of the Nile Valley must 

 always be an object of interest ; but the discovery of Professor Lep- 



