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age. Tracks of a large crustacean are numerous in the Potsdam sandstone, coprolites occur in abundance at the summit of the Calciferous sand-rock, the succeeding limestones are very rich in fossils, and the Utica slate is distinguished by abundance of bitumen, which has been used as a source of oil derived from its destructive distillation, but not, commercially, with success. The Onondaga salt group furnishes gypsum and brine springs. The marbles of the lower limestones are susceptible of a fine polish, and hydraulic cement of the best quality occurs in many part3 of the province.
The highest rock in the eastern basin is a millstone grit, which forms the base of the New Brunswick coal field. It occurs in the Peninsula of GaspS, and is underlaid by Devonian sandstone of great thickness, (7,000 feet,) which reposes on limestone and shales of the Upper Silurian Series, resting upon rock of Middle Silurian age. Some members of the Lower Silurian Series are highly metamorphosed and developed to an extraordinary extent in the vicinity of Quebec and elsewhere, showing a thickness of 7,000 feet, and distinguished by metaliferouB veins; hence, although of the age of the Potsdam sandstone and the Calciferous sandrock, they have been named the Quebec Group, also the Taconic system, and the Upper Copper-bearing rocks of Lake Superior. They are of vast economic importance, inasmuch as they form the great metaliferous formation of North America, containing gold, lead, copper, zinc, silver, cobalt, nickel, chromium and titanium. They are traceable from Gaspe to Alabama, under various designations, and thence to the west side of the Mississippi, through Kansas to Lake Superior, without suffering any diminution in volume. The copper ores in Eastern Tennessee and those of Acton in Lower Canada, belong to this important group, as well as the lead, copper, zinc, &c, of Missouri, and the copper of Lake Superior.
On the shores of Lakes Huron and Superior, the Quebec group rests unconformably on the Huronian Series, which reposes also unconformably upon the Laurentian Series. The Huronian Series is 18,000 feet thick, and consists of quartzites, thin limestone bands, slate rocks and diorite. It is the lower copper-bearing rock of America. The immense beds of iron ore at Marquette also belong to this series. It is traversed by a vast number of trappean dykes. The Laurentian system is the oldest known system of rocks, and is composed of gneiss, crystalline limestone and Labradorite. This series is of enormous thickness, one band of limestone being 1,000 feet thick, and the entire mass of altered sediments composing the vast Laurentian series probably exceeds 20,000 feet. Traces of fossils have been found in several localities; beds of iron ore hundreds of feet thick, great veins of metallic sulphurets with widely distributed crystalline limestone bands, give great economic importance to the series. The geographical surface of Canada contains about 80,000 square miles of unaltered fossiliferous rocks, and probably 230,000 square miles of the Laurentian Series. Where the Laurentian Series is not covered with quarternary deposits, the belts of crystalline limestones, and soda and lime feldspars, produce upon disintegration a fertile soil, so that the cultivable area in the Laurentian country is much greater than would be inferred from the gneissoid character of the formation in many districts.
THE CLIMATE OF CANADA.
The geographical position of Canada has necessarily a remarkable influence upon the climates of different parts of the country. The western peninsula has its climate greatly modified by the vast lakes which almost encircle it. The valley of the St. Lawrence below Kingston, as far as tide water, is removed from this ameliorating influence, and the country below Quebec is subject to many of those vicissitudes which belong to great estuaries and the sea-coast. The north shores of Lake Huron and Superior, and the back country north of a line extending from Lake Huron to Ottawa, and removed from the influence of the great lakes, possess a very rigorous climate, in which intense winter cold, prolonged through many weeks, is followed by a short but hot summer, succeeded by genial autumnal months.
Meteorological observations have been carried on for many years, at three separate points, which may represent the centers of the different climates of Canada in the settled parts of the country. At Toronto, (1862,) the mean annual temperature for a period of 22 years, has been 44°.12, the warmest month, July, has a mean of 66°.85; the coldest month on the average of 22 years is February, which has a mean temperature of 22°.98. The highest temperature recorded was 99°.2, the lowest,'—26°.5. The average range of temperature during the same period amounts to 102°.7. The average fall of rain during 21 years was 30.32 inches. The greatest rain-fall in one month was 9.76 inches, the greatest in one day, 3.36 inches; but the average for 21 years of the greatest rain-fall in one day is 2.14 inches. The average fall of snow for 21 years is 61.6 inches, and the number of days on which snow falls is 57. The total average depth of snow and rain during 21 years is 36.49 inches. The average number of days on which rain or snow falls is 163. September is the most humid month. The resultant direction of the wind during a period of 14 years is N. 60 W. The mean velocity per hour being 1.85 miles; but without regard to direction, the mean velocity is 6.78 on an average of 14 years. The mean humidity of May, June and July, deduced from a period of 21 years, is 74.
At Montreal, (1856,) the mean temperature of the air for a period of 7 years, was 41°.56. The absolute mean range for the same period has been from 90°.9 to27°.4 below zero. The highest temperature in the shade recorded was 100°.l, the lowest 36°.2 below zero, giving a climatic range of 136°.3. The degree of humidity is represented by .84. The average number of days on which rain fell was 73 per annum, and of days on which snow fell 43; or in all, 116 days on which precipitation took place. The rain-fall amounted to 43.004 inches; the depth of snow to 95.76 inches, or 52,380 inches of precipitation reduced to the form of rain. The mean of evaporation from the surface is nearly 21 inches during the spring, summer and autumn. The most prevailing wind is the westerly. The snow storms are from the N. E. by E., on the average.
The following table shows the monthly mean temperature at four different stations between the head of Lake Ontario and Quebec inclusive. From it an idea of the difference in climate between those far separated points may be inferred. The period over which the observations extend is the year 1855, but it is probable that the means of a large number of years would produce slight but comparatively unimportant changes in the observed temperatures. From this table the chief differences in the climates of the districts of which they are centers may be deduced.
Of the Mean Monthly Temperatures at Hamilton and Toronto, (Upper Canada,) and Montreal and Quebec, (Lower Canada,) for the year 1855.
M «-"i ; In Toronto. Montreal. Qubbso.
Min. 1855 ........ —20.00
Max. " ........ 96.00
The year 1855 was distinguished by the extreme and prolonged cold of February.
Showing tbe average Temperature, Humidity, Wind, Rain and Snow at Toronto, 108 feet above Lake Ontario, or 341 feet above the sea, for a period of 22
(Otjirmaory, Toronto, Professor Kingston.
Arerage of 22 yean.
Mean temperature of the year 4-1 '.12
Extreme* In 22 yean.
(in 1846.) (in 1856.)
Warmest month July. July, 1854. Aug. 1860.
when the mean temperature of the month
wag 660.85 72o .47 64o .46
Coldest month February Jan. 1857. Feb. 1848.
when the mean temperature of the month
was 22° .98 120 .75 260.60
Difference between the warmest and coldest
months 43° .87
Highest temperature 90° .4 99O .2 82O .4
which occurred on July 22 Aug. 24. Aug. 19.
. (1854.) (1840.)
Lowest temperature 12o .3 —26p .5 tl°.9
which occurred on Jan. 25. Jan. 26. Jan. 2.
Range of the year 102°7. 118Q.2 87° .0
(in 1855.) (in 1847.)
</£?£». Extreme, in 20 yean.
Mean humidity of the year 78 82, in 1851. 73, in 1858.
Month of greatest humidity January. Jan. 1857. Deo. 1858.
when the mean humidity of the
month was 83 89 81
Month of least humidity May. Feb. 1843. April, 1849.
when the mean of the month wu 72 58 76
Extreme In 9 jrem
Mean cloudiness of the year .. 60 62, in 1861. 57. in '53 '56.
( Deo. '58. )
Most cloudy month December. < Dec. '60. f- Dec. 1857.
(Feb. '61.) when the mean of the month was 75 83 73
Least cloudy month July and Aug. July, 1853. June, 1861.
when the mean of the month was 45 34 45