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allowing 100 grains for moisture, as either thecalx or argill exceeds the proportions in morefertile lands.

The specific gravity of these soils is not given;but it probably exceeds or falls short of that ofthe more fertile soils.

IN BARREN SOILS,

The proportions of Silex, from 42 to 88Argill — 20 — 30Calx — 4 — 20

Hence the troy pound contained, allowingfor water 120 grains,

Silex, from 2368 to 4963

Argill — 1128 — 162

Calx — 225 — 620

The specific gravity of these soils is not given;but it probably is either much above or muchbelow that of the former, as they are either tooclose or too open. Mr. Fabroni found that ofbarren sandy land 2,21.

Note also, that if the proportion of water bedifferent from that here supposed, the contentsof the troy pound will also be different; butmay be easily rectified.

E 4