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and is but slightly cohesive, being of a gravelly character. From its inclined position, and want of agglutinating principles, it is liable to denudation, through which all the valuable particles derived from the disintegration of felspathic minerals are carried away.
Power of absorption of solar heat - - + 10
Power of terrestrial radiation - - - — 4
Capacity for moisture - - - + 3
Solubility of 100 parts: —
Soluble in acids .... 10-00
Soil No. 38.
"Was taken from a farm on St. George's or St. Helen's river, belonging to the Honourable Mr. Talbot, and in the hands of a tenant. Granitic rocks and greenstones yielded their ingredients to the formation of the soil. Its specific gravity is 2'0; colour brown, and texture coarse. A third part of it consists of pebbles of quartz and flint; it has little cohesion, great permeability, and does not sufficiently retain water. The tenant tried wheat, oats, and potatoes, but every crop failed; so the soil was abandoned to Aveeds and rushes. It was never manured.
Belongs to the upper country of Van Diemen's Land, commonly called the Lake country. It lays among trap rocks, and may be said to be entirely composed of disintegrated greenstone, basalt, and trachyte. Its specific gravity is 1*5 ; colour, a blackish brown; cohesion moderate; is rather gritty to the touch; clogs when wet, and resists drought, as it quickly absorbs water. It is as yet untouched by the hand of man, and produces a luxuriant indigenous vegetation of grass, shrubs, and trees. This soil represents the soils of a large tract of country belonging to the Government, and needing only draining and population to be converted into a most productive district of the island. Specific gravity, 1*0.
Power of absorption of solar rays - + 12-0
Power of terrestrial radiation - - — 3-0
Capacity for moisture - - + 12-0
Soil No. 40.
Represents the soils which cover the western shores of the river Huyon. The sample refers more particularly to a property of 4000 acres, sold by William Price, Esq., to Lady Franklin, and which, subdivided in allotments of 100 and 200 acres, is, through the wonted liberality of her Ladyship, resold to small farmers of good character, at a prime cost of 12s. an acre. This sample is an average of as yet untouched ground. The soil of the whole Huyon valley is derived from the disintegration of greenstone, trachyte, and greywacke. Its specific gravity is 1*3; its colour is a darkish brown; its substance tolerably fine. It feels gritty, easily agglutinates, and is both permeable and retentive of moisture. It produces the most beautiful and valuable timber in the island, the trees exceeding 200 feet in height, and sometimes measuring in circumference thirty-six feet. Crops of wheat and potatoes succeed surprisingly. Those among the small settlers who industriously availed themselves of the productiveness of this soil, realised in one year, by the timber and potatoes alone, the prime cost which they paid for the land. Specific gravity, 1/3.
Power of absorption of solar rays - - + 16'00
Capacity for moisture - - - + 9'00
Solubility of 100 parts : —
Soluble in acids .... 41-20
Insoluble in acids .... 58'80
Soil No. 41.
Taken from one of the small farms of Delareync dictrict, which is famous for its fertile soils, derived from the disintegration of greenstone and quartz rock. The one under consideration has a specific gravity of 3'2; it is dark grey in colour, of pretty even substance; gritty when dry, rather smooth when moist; it absorbs and retains equully well the rain-water. Its appearance is good. It was cultivated without manure, and used to yield good crops of wheat for several years, but it was finally abandoned on account of sterility, brought on, as the tenant acknowledges, by continual crops of maize, which he raised without manure.
Power of absorption of solar rays - -f- 18
Power of terrestrial radiation - - — 7
Capacity for moisture - - - + 2
Solubility of 100 parts: —
Soluble in acids .... 7-00
The following tabular views represent the preceding analyses of soils in two distinct groups, — one of the highest, the other of the lowest productive power obtained:—