22 R:6suM]fi OF surbll's study op 



scale, the basin embraces vast ridges of mountains, and the outline may 

 be traced on an ordinary map. The gullet is prolonged towards the lower 

 part of the channel, forming a valley or rather a nan'ow gorge deeply 

 embanked by the flanks of the mountains, and the length of which is often 

 more than two leagues. It supplies, says Surell, the very best example I 

 could give of valleys opened up or created by the action of the waters alone. 

 In this gorge the hills are very abrupt, and miTiaeo par les pieds, cut away 

 at the base, and cut up by a great many ravines. They rise frequently 

 more than 100 mtees, or 335 feet, above the bed. At different distances 

 they are out into by secondary torrents, which are lost above in the rami- 

 fications of the contour of the mountains, and they each bring into the 

 gorge the waters collected from a part of the basin. These mountains 

 furnish to the torrents a large portion of the matter carried away and 

 deposited in the bed of dejection, and from their sides come the large blocks 

 which fall here and there into the bed of the torrent. 



He mentions that in the bassins de reception, or basins drained by torrents, 

 of the first order, there are often seen on the sides of the mountains 

 enormous blocks of stone, which sometimes fall into the beds of the torrents 

 and are then carried far by the rush of waters. In some cases there may 

 be seen standing in a vertical position, in the middle of a slope, what looks 

 tike an artificial obelisk ; such are almost always capped by some such 

 large block, which one would almost say had been placed there by the hand 

 of man. It is to this block, says Surell, that the obelisk owes its formation. 

 Originally the block lay on the surface of the slope. In this position, when 

 there came a sudden heavy fall of rain, and the water was rushing away in 

 little streamlets on the face of the mountains, this stone presented a solid 

 and indestructible obstacle which divided a current turning it off to the 

 right and to the left. It may easily be conceived that in this manner it 

 would protect the portion of the slope immediately beneath it, on which it 

 rested ; this then would remain untouched and undisturbed, while the 

 igipound around it was being dug into and carried away. At last it would 

 come to pass that the portion of the soil which had thus managed to keep 

 itself above the level of the parts washed away, forming at first a ridge or 

 a block of earth with a sharp angle, which became thinner and thinner by 

 the action of time and atmospheric disintegrating influences, took the 

 figure of a well-defined obelisk, standing out clearly from the slope. 



These obelisks are known by the inhabitants of the country under the 

 designations demoiselles, or young ladies, and nonnes, or nuns. They may be 

 seen on the mountains of the torrent of the "Graves, of that of Crevoux, of 

 Babioux, of Grenoble, of that near Brian9on, etc., etc. 



The throat or gullet widens upward at the spot where it joins the funnel, 

 and this sometimes takes the figure of a col denuded of its covering of 

 earth, which assumes the form of an amphitheatre before the embouchure 

 of tlie gullet. At other times the col forms what is called a pastoral 

 mountain — a name given to mountains appropriated to the flocks — fui-rowed 

 by innumerable currents, which there spread themselves out in the form of 

 the foot of a goose. The torrents of Rabioux and of Mauriand may be taken 

 as types of such, and so may the torrent of Baohelard, abutting on the col 

 d'Allos, in the Lower Alps. These vast depressions being situated in the 

 higher parts of the mountains, the water supply during the greater portion 

 of the year can only foil in the shape of snow. In this state it is not 

 dispersed, or is but little dispei-sed ; it is retained, it accumulates, and if 



