March 27, 1885.] 



SCIENCE. 



255 



ever, caused England to set about the undertaking; 

 and work on the road has begun. The gauge, after 

 some discussion of the relative merits of three feet, 

 three feet six inches, and other widths, has been fixed 

 at four feet eight inches and a half, probably with a 

 view to permanency. It will be necessary to use iron 

 sleepers, as the ants destroy wood rapidly. 



The question of a water-supply on the route is a 

 very important one. Col. H. G. Prout, an American 

 engineer, formerly in the employ of the khedive under 

 Gen. Stone as chief of the geographical and topo- 

 graphical section in the general staff bureau at Cairo, 



describes. From his communication the following 

 points are condensed : — 



Two miles inland from Suakin are wells which 

 yield the only water for the town. For fifteen miles 

 the route lies over a plain of gravel and small bowl- 

 ders, and rises about eight hundred and fifty feet 

 above the sea in that distance. A number of shallow 

 beds of water-courses cross this plain, dry except for 

 short and infrequent periods, as there is often no rain 

 for two or three years. There is no vegetation, except 

 some small acacias six to twelve feet high. In this 

 distance wells are found at two places, each sufficient 



L*. «l «-fl. % « 7 



contributes to the Engineering news of March 7, 1885, 

 an account of a reconnoissance of the Suakin-Berber 

 route made by him in April, 1875, and gives a map 

 and profile of the route, the essential features of 

 which are reproduced here. This profile is stated to 

 be the first one published outside of Egypt; and the 

 Manchester guardian speaks of his report as giving 

 the best information possessed in regard to the line. 

 The survey was made with care ; the longitudes of the 

 termini were taken from the best maps, and checked 

 by chronometer; the latitudes were determined by 

 his own observations ; the line of the route was kept 

 by prismatic compass-bearings and by marching- 

 time; observations for altitude were made with two 

 aneroid barometers, and carefully reduced. As the 

 survey was made in April, and as there had then 

 been no rain for two years, the English will now find 

 much the same condition of things as that which he 



for from three hundred to five hundred men and 

 their animals. Then the line enters the mountains, 

 and passes for five miles through a valley varying in 

 width from one or two miles to the bowlder-bed of a 

 mountain torrent. Here at Sinkat, a thousand feet 

 above the sea, are the wells of Hambuk, — water- 

 holes three feet deep, filling slowly, and kept drained 

 by two hundred men and their horses, and three hun- 

 dred camels. Thirty-two miles from Suakin is the 

 divide between the valleys of Sinkat and O-Mareg, 

 sixteen hundred feet above the sea, and presenting 

 the first difficulty in building a railroad, as for some 

 miles the pass is narrow and crooked, and the grades 

 steep. Masonry to protect the road-bed from the tor- 

 rent will be required, and rock-cutting may be neces- 

 sary. The defile is a very bad one to pass in the face 

 of an enemy. Thence the route lies through small 

 valleys, with a growth of low trees and shrubs for 



