FIFTEENTH ORDINARY MEETING. 203 
illustrates in an interesting manner several of the peculiar differences 
due to situation. Like Toronto it is exposed to the northerly winds 
modified by the Georgian Bay a hundred miles to the northward, but 
it is in a measure protected from the north-easterly winds by the 
intervention of Lake Ontario, More important in its bearing on the 
climate is the fact that the southerly and south-westerly winds which 
in reaching Toronto, have part of their warmth abstracted by Lake 
Ontario, reach Hamilton after blowing over a considerable stretch of 
land. Hence the latter place attains much higher temperatures in all 
seasons of the year than are reached on the north shore: the mean 
temperature is also higher, In addition to these causes which tend 
to increase the daily and seasonal range, the situation of the city on 
a low plain with a steep escarpment on the south and a range of hills 
across the bay on the north, tends to the existence of great daily 
contrasts, for in certain conditions of weather, the heat appears to 
accumulate in the sheltered “ ravine” while in other conditions the 
heavy cold night air of the upland pours over the ‘‘ mountain” and 
displacing the warm air, settles beneath it. 
A remarkable instance of the effects of situation in a ravine, 
cutting through an extended upland, is afforded by the records of Galt 
on the Grand River. In 1879 the writer had charge of the meteoro- 
logical station in the valley of that town. On the edge of the 
plateau tothe west, a little more than a mile distant from the ravine 
station and about 180 feet higher than the later, was a second station 
in charge of a careful observer, Mr. Alex. Barrie. The thermometers 
at both stations were protected by the fence and screens approved by 
the meteorological service and in use at Toronto Observatory, and 
great care had been exercised to make the conditions of exposure 
similar. Here while the average daily maximum temperature was 
about two degrees higher at the valley station than on the plateau, 
the relative temperatures were sometimes greatly reversed. On Oct. 
10th 1879, the maximum at the plateau station was 90°.3, while at 
the valley station it was but 79°.3, eleven degrees lower. On another 
date in the same year the difference was still greater, the thermome- 
ter at the 9 p.m. reading on the plateau being 79°, when in the valley 
it was only 65°, or fourteen degrees lower. There being no station at 
Hamilton, other than in the valley, similar instances there of the 
inflow of cold air cannot be cited. But the effect of this occasional 
inflow is seen in the facts that while the mean temperature and 
