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NEW YORK STATE MUSEUM 



Vicars. The northern slope of this hill thus stands as a self- 

 registering nilometer of the water levels which have existed in 

 the St Lawrence valley in contradistinction to glacial lake levels 

 in the Chaniplain on the east of the Adirondacks and in the upper 

 St Lawrence valley and over the Lake Ontario basin on the west. 



The crest of Covey hill is till covered. It has already been 

 pointed out that " the Gulf " at the western base of the hill 

 indicates the path of a powerful torrent flowing across this spur 

 of the mountains at the time when the ice front had receded locally 

 as far as Covey hill, but had not retreated from its northern 

 slope. These torrential waters held up by the ice formed a water- 

 fall, whose cliff is now at 870 feet, and whose pool stands at 

 830 feet; below this is a second pool in the bottom of a chasm 

 160 feet deep precisely on the international boundary line. The 

 surface of this pool, according to Dr Gilbert's observation, is 

 645 feet. From this point the valley opens out, the small, spring- 

 fed stream which escapes from the lakelets turns northeastward, 

 thence north past Covey Hill postoffice and, joining the English 

 river, falls into the Chateaugay and thence enters the St Law- 

 rence river at a point almost directly north of Covey hill. 



From the facts shown at " the Gulf " it is evident that, when 

 the ice front rested against the northern slope of Covey hill, 

 the drainage at its southern base found open-air conditions of 

 flow at a level as low as that of 645 feet. About 2 miles south- 

 east of this lakelet, something like shore line phenomena appear 

 on the Mooers quadrangle at 620 feet to 630 feet, a level which 

 would not have drowned the waterfall action at " the Gulf." 

 At an earlier stage water levels appear 100 feet higher in the 

 northwest corner of the Mooers quadrangle; water at this level 

 would have penetrated the chasm at " the Gulf " and entered part 

 way between the lower and the upper lakes. At a still earlier 

 stage there appears to have been formed a cobblestone bar with 

 spits just west of the Mooers quadrangle at an elevation of about 

 810 feet (aneroid) ; waters at this level would have come nearly 

 to the upper lake. 



At the time the waters were flowing out of the lower lake at 

 " the Gulf," the discharge must have taken place eastward and 

 thence southward to the Mooers quadrangle along the 620 foot to 

 640 foot level, being held to this line of flow by the ice on the north 



