chap. vm. RIDGES IN NEIGIinOURIIOOD OF THE ECRINS. 149

glance on the accompanying map, which is a reproduction of a por-tion of sheet 189. The main ridge of the chain runs, at this part,nearly north and south. Eoche Faurio, at the northern extreme, is3716 metres, or 12,192 feet, above the level of the sea. The lowestpoint between that mountain and the Ecrins (the Col des Ecrins) is11,000 feet. The ridge again rises, and passes 13,000 feet in theneighbourhood of the Ecrins. The highest summit of that moun-tain (13,462 feet) is, however, placed a little to the east of and offthe main ridge. It then again falls, and in the vicinity of the Colde la Tempe it is, perhaps, below 11,000 feet; hut immediately to thesouth of the summit of that pass, there is upon the ridge a pointwhich has been determined by the French surveyors to bo 12,323feet. This peak is without a name. The ridge continues to gainheight as we come to the south, and culminates in the mountainwhich the French surveyors have called Sommet de l’Aile Froide.On the spot it is called, very commonly, the Alefroide.

There is some uncertainty respecting the elevation of this moun-tain. The Frenchmen give 3925 metres (12,878) as its highestpoint, but Mr. Tuckett, who took a good theodolite to the top ofMont Pelvoux (which he agreed with his predecessors had an eleva-tion of 12,973 feet), found that the summit of the Alefroide waselevated above his station 4'; and as the distance between the twopoints was 12,467 feet, this would represent a difference in altitudeof 5 metres in favour of the Alefroide. I saw this mountain fromthe summit of Mont Pelvoux in 1861, and was in doubt as to whichof the two was the higher, and in 1864, from the summit of thePointe des Ecrins (as will presently he related), it looked actuallyhigher than Mont Pelvoux. I have therefore little doubt but thatMr. Tuckett is right in believing the Alefroide to have an elevationof about 13,000 feet, instead of 12,878, as determined by the Frenchsurveyors.

Mont Pelvoux is to the east of the Alefroide and off the mainridge, and the Pic Sans Nom (12,845 feet) is placed between thesetwo mountains. The latter is one of the grandest of the Daupliine