The locus classicus for the discussion of extensive and intensive
cuftivation is Prince Kropotkin's Fiekls, Factories and Workshops. Since he wrote, partly in order to demonstrate that a very small area of land could support a very large population, intensive facilities have immensely increased. Glass is more easily manufactured: Artificial heat is more easily and cheaply supplied. Science has discovered the cure for many of the diseases that affect much= used soils. The glass-house gardeners both sterilize the comparatively small amount of soil needed for starting their plants, and at two year • intervals treat the whole ex- panse with sufficient heat to kill fungus and insect pests. The worker in- the English glass-house does not undergo the drudgery that Kropotkin noted in the French gardener, who produced some £600 an acre by frames and cloches and manurial heat. The glass age may be just beginning.
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