3i8 The American Geologist. ^^y- i^*'*- 
its existence. Very careful search revealed one or two rocky 
shelves on the southwest side which might have been cut or mod- 
ified by wave action, but there is not enough evidence to war- 
rant such an assertion. 
On the western side of the island where the exposure to 
wave action is more complete a fairly well developed pebble 
beach was traced for a few rods at a hight of thirty-two feet 
above the bay. This was the only definite trace of an old shore 
line that was discovered. 
A number of other rocky islands and a few high points on 
the adjacent mainland were visited, but a hurried examination 
discovered no traces of old shore lines. 
On a high point of the mainland about four miles northeast 
of the northern extremity of Giant's Tomb island and about 
forty or fifty feet above the bay are several pot-holes locally 
called the "Indian kettles." These pot holes are three or four 
feet in diameter and six to eight feet deep. They are cut in the 
Laurentian rock a few rods back from the mouth of one of the 
branches of the Go Home river. 
The traces of the old water levels among these islands are 
evidently to be sought with the best success upon the high isl- 
ands of glacial materials as is shown by the results of the ex- 
aminations of Beausoleil and Giant's Tomb islands. 
The descriptions of Hope, Beckwath and Christian islands 
in the "Georgian Bay Pilot" indicate that they are largely com- 
posed of glacial drift, and it is hoped that at a future time these, 
as well as other islands further north, may be examined, where 
it is hoped that further records of the old water levels will be 
found. 
