392 Canadian Record of Science. 
the greater part; had been removed by glaciation. He 
noticed that these limestones are rich in petroleum; 
this has been observed by others also, for in answer to en- 
quiries recently made, I find that a gentleman of Buffalo 
has purchased land near Chambord with the intention of 
bringing the petroleum there into use. 
hake St. John is 300 feet above the level of the Gulf of 
St. Lawrence, it is not, except towards the centre, very deep, 
and having sandbanks in some parts, navigation near the 
Shore is difficult. In shape it is almost circular. Its 
greatest diameter from the Metabetchouan to the Peribonca 
is twenty-eight miles, and from the grand discharge at the 
head of the Saguenay to the Ouiatchouanish twenty miles. 
It is the recipient of several rivers, large and small, 
draining a great extent of country. On the north it 
receives the Peribonca, said to be nearly 400 miles long, 
and navigable for nearly twenty miles. The Mistassini 
and the Ashuapmouchouan navigable for eight miles 
coming from the north-west. On the south of the lake are 
the Ouiatchouan, leaping over and down the mountain side 
in magnificent and beautiful falls, which give the name to 
the river, and which are 236 feet in height, and the 
Metabetchouan from Lake aux Rognons, a few miles south- 
east of Cedar Lake. This river is said to have a fair 
amount of good land, suitable for settlement on its borders. 
As is well known, Lake St. John discharges its surplus 
waters by the Saguenay river into the St. Lawrence. 
It would appear as if Lake St. John occupies a hollow 
formed by the elevation of the Laurentian hills in this part. 
That in the Paleozoic times it was, with the country around, 
covered by the Silurian seas. After these retired, this part 
of the country was not much disturbed by the various 
movements which occurred in many other regions. In the 
glacial period, it was with the rest of this part of the 
continent again submerged, and much of the limestone 
carried away. The bottom of the lake and parts of the 
country around have retained the covering of Silurian lime- 
stone and the decay of this, mixed with the disintegrated 
