PHYSIOGRAPHY OF THE ADIRONDACKS. 203 



down moderate slopes from the northwest, against high and sparsely 

 wooded precipices on the southeast and join larger streams which flow 

 northeast or southwest. When a wide area is studied, it is only 

 the older and still surviving east and west or north and south valleys 

 which break up this lattice-like regularity. 



In less frequent occurrence than the northeast and northwest fault 

 breaks, minor ones ranging nearly due north may be recognized — but 

 they do not exercise so important an influence on the general relief. 



The -three systems of faults have in some instances led to great 

 single precipitous escarpments suggesting that the movement was 

 chiefly confined to one single plane, but it is much more common to 

 find the fault a compound one. That is, a very steep mountain face 

 will consist of a series of small escarpments, each with a bench at its 

 foot. These benches make terraces, and on Lake George one can 

 easily see, even when the mountain is thickly forested, that the trees 

 are growing in pronounced rows with thinner lines of vegetation be- 

 tween. A mountainside may thus look like a gigantic series of fur- 

 rows, as is true of the ridge from Black Mountain to Elephant Moun- 

 tain. Where the faults cut across a projecting shoulder the terraces 

 gc up one side and clown the other like a series of lunettes. Forest 

 fires and the lumberman's axe, while destroying much of the beauty, 

 have yet brought out these features with striking emphasis, and when 

 the light intensifies the relief with shadows they appeal to the observer 

 in the strongest way. The narrow ridge between Lake George and 

 Lake Champlain contains some of the roughest country in all the 

 Adirondack region. 



The faults and their escarpments were doubtless much freshened 

 up b} r the Labradorean ice-sheet which plucked away from their faces 

 the loose rock, sheeted by the parallel faults. In this way the relief 

 was heightened during the Glacial epoch, and its freshness and youth 

 still remain to us, but the faults preceded the ice and were the great 

 governing factors. Thus far no evidence of post-glacial faulting has 

 been observed. 



On the south side of the mountains the faults run out in a striking 

 way into the overlapping Paleozoic areas and have been traced as much 

 as thirty or forty miles. One famous one causes the Precambrian 

 rocks on the west to abut sharply for thirty miles against the Cam- 

 brian and Ordovician strata, forming an escarpment which faces east. 

 After the Precambrians have disappeared below the Paleozoics for two 

 miles, they rise again into view at the pass called the ' Needles/ where 

 the Mohawk river, the Erie Canal and the New York Central and West 

 Shore Railways find a way close together fifty miles west of x\lbany. 

 Another is responsible for the Precambrian outlier of Little Falls, re- 

 cently described by Professor H. P. dishing. The displacements ex- 



