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periments, already mentioned, and as Mr. Has*senfraz, who repeated this experiment, ob-served. Rain-water might however supply asmall quantity of calx sufficient for a small pro-duce of corn.

I pass over his experiments on old mortar,as the three earths were evidently contained init, though in unknown proportions.

Soils on the declivity of hills ought to bemore retentive of water than those on plains,as is evident.

CHAP. III.

TO DETERMINE THE COMPOSITION OF A SOIL.

jm:>. ijj dry weather, when the soil is notover moist nor dry, let a surface of l6 squareinches be cut through to the depth of 8 inches;this may be effected by a right angled spade,formed for this particular purpose. Of the