TWENTY-EIGHTH ANNUAL MEETING. 23 
THE CLOSING OF MICHIGAN GLACIAL LAKES. 
* By B. B. SmytuH, Topeka. Read before Academy January 3, 1896. 
Livingston county, Michigan, is near the center of the state; and while its 
elevation is not great above the lakes, yet it is about the highest land in central 
Michigan. The waters from it run northward into Lake Huron, westward into 
Lake Michigan, and southeastward into Lake Erie. 
There is very little native rock exposed in the county ; there is a heavy mantle 
of drift nearly all over the county, in many places exceeding 100 feet in depth. 
This drift varies in its nature in different parts of the county: in some places it 
consists largely of clay thickly interspersed with rounded pebbles and boulders 
from four inches to perhaps two feet in diameter ; in other places the drift con- 
sists largely of gravel and water-worn pebbles to a depth of 20 to 40 feet, and 
again it consists of sand and clay heaped up into what is known as “short hills,’’ 
often to a height of more than 100 feet. Moraines of stone are frequent, and 
nearly always run due east and west, occasionally varying to south of east and 
north of west. 
Those high hills and drift lands are by no means the barren lands one might 
be led to suppose. Much of the drift is mixed with a large proportion of lime, 
or limestones, carried from hills not very far remote ; and the presence of stones 
on the surface seems to have a tendency to warm the soil and hasten the growth 
of crops. 
On many farms the stones are so thick on the surface that it is impossible to 
plow without removing the larger part of the stones to a depth that will permit 
plowing. These stones, although they entail much labor on the farmer, are a 
source of wealth after all; they furnish material for all the fences needed, besides 
houses and other buildings. Allow me to describe one, that of Mr. Riddle, of 
Osceola township, which is representative of a great many of the wealthier farms 
of the county, especially of that township. 
Derirt PEBBLES. 
Miles of stone fence, four feet high, are to be seen. Some of these fences, 
especially those running alongside the main road, are built with an eye to artistic 
beauty. The base consists of a layer of heavy, rounded, gray granitoid stones; 
then follow a couple of layers of smaller water-worn pebbles of nearly uniform 
size and about 10 inches in diameter; then a layer of heavy red quartzite about 
10 inches in thickness; then again several layers of white rounded pebbles, finally 
capped with a layer of broad greenstone schist and blue limestone. Barn and 
other buildings are built of the same kinds of stone. 
The house, which is quite a roomy one, is built almost entirely of ovoid peb- 
bles about 5 by 8 inches in diameter and 11 inches in length. These pebbles are 
very uniform in size and laid up in the cementing material in herring-bone style: 
First, on a solid foundation of quartzite or granitoid boulders, a horizontal row, 
nearly on end, slanting upward to the right, next a row slanting upward to the 
left, and so on alternately, making the pebbles stand in zigzag fashion. An oc- 
casional binding layer of larger boulders of a different color is put in, the upper 
layer being especially heavy. The corners and door and window posts are of 
larger stones of different color laid flatwise; the lintels are of greenstone trimmed. 
The house has the appearance of having been quite recently built, but an inquiry 
