134 Observations on Sculptured Marks on 



who had succeeded in making a series of barometrical measurements 

 along the Nile Valley, from the Mediterranean to Sennaar and Kordo- 

 fan, and thence to the 10th degree of north latitude. He gives the 

 following altitudes, above the sea : — 



Paris Feet. Enj?lish Feet. 

 The upper part of the Cataract of Assuan, 342 = 364*37 

 Korusko, on the right bank of the Nile, 



Nubia, 

 Wadi-Halfa, . 

 New Dongola, . 

 Abu Hammed, 



450 = 479-43 



490 = 522-00 



757 = 806-52 



963 = 1026-00 



I shall now give the length of the Nile along its course from Abu 

 Hammed to the island of Philse, at the head of the cataract of 

 Assuan. I employ for this purpose the map in the atlas which ac- 

 companies the work of Russegger, which bears the date of 1846, 

 and which, doubtless, was constructed on the best authorities. He 

 mentions a map of General von Prokesch with great praise.* It 

 flows : — 



German M. English M. 

 From NE. to SW., from Abu Hammed to 



Meroe, about . . . 31 = 150 



It makes a curve between Meroe and Old 



Dongola, of about . . 16 = 77 



It flows between Old and New Dongola, 



from SE. to NW., about . 16 = 77 



Then, with some short windings, nearly due 



north to the island of Sais, for about 30 = 145 



And from Sais to the island of Philae, from 



SW. to NE., about . . 68 = 327 



Making the whole length of the course, from 



Abu Hammed to Philae, about . 161 = 776 



Ascending the river, we have, between Philae and Korusko, a dis- 

 tance of 24 German, or \lb^ English miles, and without any rapid, 

 except one near Kalabsche. Korusko being 115 feet above the head 

 of the cataract of Assuan, at Philae, we have an average fall of the 

 river between these two places of a foot in a mile. 



Between Korusko and Wadi-Halfa there is no rapid. The dis- 

 tance being 20 German, or 96^ English miles, and the difference of 

 altitude being 42^- feet, we have an average fall throughout that part 

 of the river's course of not more than 5-3 inches in a mile. 



This very inconsiderable fall need not surprise us ; for the average 



* " Uber den Stromlauf und das zunachst liegende Uferland des Nils, von der 

 zweiten Katarakte bis Assuan, besitzen wir eine vortreffliche Karte namlich :" 

 " Land zwischen der kleinen und grossen Katarakten des Nil. Astronomisch 

 bestimmt und aufgenon)inen in J. 1827, durch v. Prokesch. Nil Grundrisseder 

 Monumente. Wien, 1831."— Reisen Bd. ii., Thl. iii. 86. 



