in Reply to Mr. Reke. J 99 



portion of the argument. I have not found it. The mere 

 fact that rivers form deltas and produce more or less changes 

 on the surface, and that these rivers have done so, no one dis- 

 putes. I believe this delta's existence is now disproved by 

 history. But a word or two on the desired topic. 



There seems no other doubt than that in discussion, that 

 all below Felujah, or thereabouts, in the course of the Eu- 

 phrates, has been, at some period, geologically modern, a part 

 of the desert, and, like all sandy deserts, once covered by the 

 ocean : that accounts for its level character. And, from the 

 tendency which the waters of an inlet of the ocean, like that 

 supposed, have to rise, as have long been known in the instance 

 of the Red Sea, I fear, paying no respect even to the wide 

 boundaries now given to it, it must necessarily have travelled 

 over all the Arabian desert. What was to stay it? The gulf 

 current drives that way. The protecting slip of country was 

 not yet raised by the ordinary deposits of the river. The 

 measure of this delta is clearly the extent of the level. That 

 slip is no true exception. On the principle adopted, all the 

 desert has an equal claim. But in forming deltas, rivers do 

 not construct sandy deserts; so that is excluded. 



In the opening made by Alexander to the Pallocopas, in 

 order to limit the efflux of water, and therefore, probably, at 

 no great depth, the workmen appear to have come to rock 

 within about 30 stadia of the Euphrates, v7T07rsTpo$ r\ yrj e$«i- 

 viTcti. From the context this was plainly not mere gravel, — 

 a very unlikely discovery many miles laterally within, and 

 some 200 from the head of, a delta *. 



A river, in producing a delta, forms both its own bed and 

 channel necessarily, at first, in the proximate line of its course. 

 If it can thus obtain a sufficient slope, (and where does it?) 

 the channel thus formed will also necessarily be nearly straight; 

 but as the inclination which its delta acquires, in either a di- 

 rect or transverse line, must be very moderate, the stream na- 

 turally divides into several channels. Both these rivers, how- 

 ever, and especially the Tigris, instead of pursuing a direct 

 course, are here tortuous and serpentine, and, for the most part, 

 keep each within a single channel. The Tigris passes over 

 the alleged delta in a rapid stream, consequently finds a con- 

 siderable slope; the Euphrates from above Felujah, for upwards 

 of 600 miles, in a dull and lingering stream, consequently with 

 scarcely any, and to its low level the Tigris, " very different 

 in every respect f", at length bends its course and joins it at 



* Arrian, Expcd. Alex., 1. vii.c. 21. 



t Col. Chesney's Evidence and Remarks in Report. 



