308. Notice of the Peninsula of Michigan. 
and sienite on parts of the shore of lake St. Clair, and rolled 
stones in Oakland and other counties. But of rocks in situ, 
few sections of our eases are so destitute of accessible | 
for : economical ses; though there are indications that 
many districts of the peninsula, where no rocks appear, have 
a calcareous basis. Sinks which are rarely observed except 
in limestone countries, are often seen in the undulating inte- 
pe s are there’ found copiously depositing calcare- 
us tufa. xtensive beds of limestone occur in lakes Michi- 
par 
the western declivity. Limestone and sandstone ledges are 
located in the north-western part of the peninsula, on the 
shores of lake Huron and the banks of Flint river, where 
slate embracing. ge Ae 58 sulphur, and indications of coal — 
— Coal has been discovered on another branch of the 
A considerable part of lake St. Clair is reported to have a 
limestone bed, often covered by a thin stratum of sand. The 
connecting streams, St. Clair and Detroit, contain limestone 
rocks in situ..§ From an island situated — latter river, 
eighteen miles below Detroi © sup 
building stone are quarried. “It is seco 
coloured piemetes is easily wrought, and is 
ontian hav : 
5 2 e beds of pearae containing petrifactions of marine 
shells, occur on the riv ouse, commencing about fifteen’ 
miles Sean its ee in lake Erie. Most of the nume- 
rous islands in the western part of lake Erie, are based on 
or ighaies limestone, and bordered by ledges of Site ‘nines 
= extensive tracts of the north-western part. of the 
cent state of Ohio, the soil rests on limestone... hat 
rock have been py are neal mien in seers  partot ie 
i 
ochre -_ oint desuer springs are common. 
solution a profitable quantity of ian of f soda. 
ble that se ss Ate may be obtained by boring. ‘i . 
ree count is a very strong and copious. 
