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Here we see the quantity of calx much greaterthan in the soil of Turin , where the fall ofrain is greater ; for in the drier climates thereis a necessity to retain the rain, and the argillif increased would retaiu it too long and toomuch; and, besides, enters very sparingly intothe constitution of plants.

The following experiments were made byMr. Tillet, at Paris , where the fall of rainamounts to 20 inches at an average.

He filled with mixtures of different earthsa number of pots twelve inches in diameter atthe top, ten at the bottom, and seven or eightdeep. It appears also, that they were so porousas to absorb moisture, and that they were per-forated at the bottom. These he buried up tothe surface in a garden, sowed in each somegrains of wheat, and then abandoned them tonature.

FERTILE MIXTURES.

1st. The first mixture he found fertile, con-sisted of three-eighths of the potters clay ofGentilly =: 0,375, three-eighths of the parings