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that of calx is 30; and in the climate of Paris,which is still drier, the proportion of silex isonly from 4 6 to 51, and that of calx 37,5per cwt. and hence we may perceive the ne-cessity of attending to the average quantity ofrain to judge of the proper constitution of fer-tile lands on fixed principles. The quantity ofrain differs much in different parts of the samekingdom; but in general in Ireland , I believeit to be between 24 and 28 inches on an ave-rage.

In the two last mixtures the proportions varyconsiderably: The first may serve as a modelfor the heavier soils, and the second for thelighter. In these and the following experi-ments, the carbonic principle seems to havebeen extracted from the surrounding garden-mould with which the pots communicated, bymeans of their perforation, at bottom.

BARKEN MIXTURES.

FIRST.

Mr. Tillet, in his sixth and eighth expen-