110 Canadian Record of Science. 
ten to twelve fathoms. Off Cedar Island the bottom may 
have suffered by the disturbances which affected the 
whole Laurentian area, as I have found there the greatest 
depth of the harbour—seventeen fathoms. 
The precise area occupied by the paleeozoic rocks in the 
environs of the city, and their age, have not hitherto been 
as accurately defined as is desirable, and a brief reference 
to these and the Laurentian rocks is necessary. 
LAURENTIAN ROOKS. 
The Laurentian rocks arc met with in great masses at 
Kingston Mills, and thence eastward and north-westward, 
forming here and among the Thousand Islands the gneissic 
ridge, as it were, which connects the Laurentian areas of 
New York State with those of Canada. Nearer Kingston, 
these rocks appear on the summit of the Fort hill, on the 
banks of Haldimand Cove, and on Cedar and Milton Islands, 
in each case forming ridges which—as elsewhere among 
the Thousand Islands—lie in a general north-east and 
south-west direction. The Laurentian strata have been 
here elevated into these great ridges at a period subsequent 
to Black River times, as, on the Fort hill, the limestone 
strata are tilted up at a high angle on both sides of the 
steep ascent, and overlie the Laurentian from the base to 
almost the summit, which is crested with gneiss.’ On the 
north side of Cedar Island the limestone strata are also 
seen near the water’s edge in a similar but less tilted posi- 
tion. Again, there are not wanting some indications, near 
the granite quarries on the banks of Haldimand Cove, that 
the granitic rocks here are not earlier in age than the 
1 My friend, Mr. Frank D. Adams, informs me that at Lake St. John limestone 
rocks of lower Silurian age, with similar dips at their immediate contact with the 
sloping gneiss floor on which they were deposited, have been found by the 
Geological Survey officers in reality in their natural beds as deposited, the 
material having apparently rolled off, as it were, from the apex and Jower down, 
and adjusted itself in sloping beds on the sides. In this instance at Kingston, 
however, the evidence of upheaval is distinct, and I am glad, since this paper 
has been put into type, to have the corroboration of so careful an observer as 
Prof. James Fowler, of Queen’s University, Kingston, who writes that ‘‘ the 
breaks in the strata and the dip towards the bridge on the one side and the river 
on the other, look as if the elevation took place after the Black River was laid 
down.” 
