"What chiefly attracts the gardener to the great cities is stable ; and this is not wanted so much for increasing the richness of the soil—one tenth part of the manure used by the French gardeners would do for that purpose—but for keeping the soils at a certain temperature. Early vegetables pay best, and in order to obtain early produce not only the air but the soil as well must be warmed... by putting great quantities of properly mixed manure into the soil; its heats it..."