^0.2.1 SCUDDEE ON GEOLOGY OF FLORISSANT, COLORADO. 281 



taking the track — half road, half trail — wliich leads over the divide 

 toward Canon City, we shall pass between the Platte Eiver and the 

 Arkansas divide, through the entire length of the basin. This road 

 crosses the South Platte a short distance, say a kilometer and a half, 

 below the mouth of Twin Creek, climbs a long, gradual slope on the east 

 bank of the river to an open, grassy glade, about 2,500 meters above the 

 sea, and then descends a little more than three kilometers from the river 

 to join the valley of Twin Creek. We scarcely begin the descent before 

 our attention is attracted by the outcropping of drab-colored shales which 

 continue until almost the very summit of the divide is reached and the 

 descent toward the Arkansas begun, a traveling distance of not far from 

 thirteen kilometers. 



By climbing a neighboring peak, thrice baptized as Crystal Mountain, 

 Topaz Butte, and Cheops Pyramid, we obtain an admirable bird's eye 

 view of the ancient lake and the surrounding region. To the southeast 

 is Pike's Peak ; to the west, South Park aud the caiion of the South 

 Platte, shown by a depression ; to the extreme south, the grand caiion 

 of the Arkansas ; while to the north a few sharp, ragged, granitic peaks 

 surmount the low wooded hills aud ravines characteristic of the nearer 

 region. Among these hills and ravines, and only a little broader than 

 the rest of the latter, lies, to the south, the ancient Florissant Lake 

 basin, marked by an irregular L-shaped grassy meadow, the southern 

 half broader and more rolling than the northwestern, the latter more 

 broken and with deeper inlets. 



Eecalling its ancient condition, and it will appear that this elevated 

 lake must have been a beautiful, though shallow,* sheet of water. 

 Topaz Butte, and a nameless lower elevation lying eight kilometers to 

 its southwest, and which we may call Castello's Mountian, guarded the 

 head of the lake upon one side and the other, rising three or four hun- 

 dred meters above its level. It was hemmed in on all sides by nearer 

 granitic hills, whose wooded slopes came to the water's edge; some- 

 times, especially on the northern and eastern sides, rising abruptly, at 

 others gradually sloping, so that reeds and flags grew in the shallow 

 waters by the shore. The waters of the lake penetrated in deep inlets 

 between the hills, giving it a varied and tortuous outline; although 

 only about sixteen and a half kilometers long and very narrow, its mar- 

 gin- must have measured over seventy kilometers in extent. Still 

 greater variety was gained by steep promontories, twenty meters or more 

 in height, which projected abruptly into the lake from either side, nearly 

 dividing it into a chain of three or four unequal and very irregular open 

 ponds, running in a northwest-southeast direction, and a larger and less 

 indented sheet, as large as the others combined, connected with the 

 south westernmost of the three by a narrow channel, and dotted with 

 numerous long and narrow wooded islets just lising above the siu'face. 



* TJio shallowness of the lake is indicated by the character of the fish, the sun-crack- 

 ing of 60iu(5 of the shales, ami the erect sequoia stumps. 



