The Westward Trains. 
501 
mingles its drift to any extent with that belonging to the later 
trains, yet this finally emerges from their area and is deployed 
on the west margin of the drift covered area. 
Its distribution is most distinctly traced from the Mud Lake 
ledges, where, owing to the marginal position of the outcrops 
the area of bowlder distribution is entirely separate from each 
of the succeeding trains. 
Bowlders from the east ledge are first found on the surface of 
the low drumlin ridge which lies in the marsh directly east of 
the main ledge of the area. Here about one hundred blocks of 
much weathered quartzite were noted on the surface of a culti¬ 
vated field or gathered into fence walls on its border, from an 
area of a few acres northeast of the adjacent ledge. As many 
more appear on the low ridge just west of the main ledge near 
the edge of the marsh. On the east slope of the ridge area 
west of the marsh basin they appear in considerable numbers. 
The northern limit of their distribution appears in a railway 
excavation at the point where the track ascends from the marsh 
on the north line of the township and nearly two miles west 
from the smaller ledge. Here about twenty large bowlders are 
left exposed on the sides and over the bottom of a pit formed 
by the removal of material for the railway grade. These are all 
from the ledge area to the east and appear to be but a small 
fraction of the material of this origin which was exposed in 
the excavation, simply the material too large for convenient 
removal. 
Quartzites are numerous on the ridge slope adjacent to the 
marsh for the next half mile south. On the east side of the 
ridge on section four, directly west of the main ledge, 
something over thirty blocks of quartzite were seen, aggregat¬ 
ing one and one-fourth cords. On the ridge surfaces, however, 
for a mile to the west the quartzites are conspicuons by their 
absence though the drift is unusually stony, and hundreds of 
cords of weather worn and glaciated Archsean bowlders are 
gathered into stone fences. A careful search through these 
accumulations revealed only a half dozen blocks of local origin 
in nearly two miles of such material. This feature is noticeable 
34 
