208 PROCEEDINGS OF THE CANADIAN INSTITUTE. 
lakes. At Galt, lat. 43° 20’, altitude 870 feet, the mercury usually 
rises to 95°, and has exceeded 100°. London sometimes records a 
higher July mean than even Hamilton or Windsor. At Zurich, 
towards Lake Huron, 103° was reported in 1881. Perhaps as forci- 
ble an illustration of the tendency of the interior to develope extreme 
heat as can be given, is in the fact that while in 1881, at Brantford, 
lat. 43°10’, altitude 720 feet, there were in May 7 days, in July 21 
days, in Augast 16 days, and in September 7 days—51 in all—on 
which the mercury rose above 90° in the shade, and while the highest 
temperature was 99°, in Toronto there were but five days, in all, on 
which a temperature above 90° was reached, and the very highest 
was only 92°.7. Towards the south-western portion of this inland 
district, the absence of lake water to the south-west, between the 
foot of Lake Huron and the head of Lake Erie, fully admits the 
south-west wind, which is usually warm, and winter temperatures 
comparatively high are often recorded. An indication of the general 
climate of this Lake Erie slope is that the peach is grown, on suitable 
soils, to an elevation of about 1,000 feet above the sea. 
In much of the interior of peninsular Ontario, thunder storms are 
numerous and more severe than on the north shore of Lake Ontario. 
Tornadoes also occur more frequently, though they are not so violent 
nor so frequent as in equal areas in Ohio, Indiana and the Cen- 
tral Western States. The snowfall of the Lake Erie slope rapidly 
diminishes as the distance from Lake Huron increases. North-west 
winds which near Lake Huron and in the highlands of Grey, bring 
several inches of snow in a single day are usually snowless over the 
southern half of the peninsula. At Galt the average duration of sleigh- 
ing is not more than six weeks ; southward and south-westward the 
period decreases to a few days. The advent of spring is one or two 
weeks earlier over much of the southern part of the district, than at 
Toronto, and winter-wheat harvest is almost as much earlier. Har- 
vest usually commences in the beginning of July and has been 
known to begin in the end of June, as far northeast as Galt, and 
about the 15th of June a short distance north of Lake Erie. 
The climate,of Windsor on the Detroit River, lat. 42° 19’, altitude 
604 fect, is fairly representative of the climate of the extreme south 
western part of Ontario. Immediately to the north is Lake St. 
Clair, and not far beyond that lake, Lake Huron, affording protection 
from the cold north winds of anti-cyclones passing eastward north 
