486 



riiOCEMJINGS OF THE NEW YORK MEETING 



The inhabitants on the spot were so much alarmed that the)' naturally did not 

 observe the actual progress of the landslip with great precision, ])ut eye-witnesses de- 

 scribe the passage of blocks and pyramids of clay through the orifice to the river 

 valley as being very swift and resembling steamers in motion on a river. The oc- 

 currence, in fact, may be said to have reseml)led the bursting out into the valley 

 of a lake of liquid mud, bearing with it outstanding and unbroken blocks of clay 

 detached from the sides of the collapsing area. 



Figure 1. — Sketch-plan showing Area of Landslip {horizontal lining). Part of Clay-filled River-valley 

 (vertical lining), and approximate Boundary of an ancient Landslip of the same Kind 



On entering the Blanche valley the flood of clay spread upstream for some 500 

 or 600 feet, ponding back the river water, but the greater part, descending the 

 valley for nearly two miles, filled it for that distance to a maximum depth of fully 

 25 feet, causing the destruction of the rich meadows along the valley, besides that 

 of the agricultural lands immediately aifected by the collapse. 



When examined by me, the actual landslip was represented by a depressed area 

 bordered by clay cliffs from 15 to 30 feet high, 1,700 feet in maximum width, with a 



