In this way man emancipates himself from climate, and at the same time he avoids also the heavy work with the hot-beds, and he saves both in buying much less manure and in work. Three men to the acre, each of them working less than sixty hours a week, produce on very small spaces what formerly required acres and acres of land.
The result of all these recent conquests of culture is, that if one-half only of the adults of a city gave each about fifty half-days for the culture of the finest fruit and vegetables out of season, they would have all the year round an unlimited supply of that sort of fruit and vegetables for the whole population.
But there is a still more important fact to notice. The greenhouse has nowadays a tendency to become a mere kitchen garden under glass. And when it is used to such a purpose, the simplest plank-and-glass unheated shelters already give fabulous crops—such as, for instance, 500 bushels of potatoes per acre as a first crop, ready by the end of April; after which a second and a third crop are obtained in the extremely high temperature which prevails in the summer under glass.
I gave in my "Fields, Factories, and Workshops," most striking facts in this direction. Sufficient to say here, that at Jersey, thirty-four men, with one trained gardener only, cultivate thirteen acres under glass, from which they obtain 143 tons of fruit and early vegetables, using for this extraordinary culture less than 1,000 tons of coal.
And this is done now in Guernsey and Jersey on a very large scale, quite a number of steamers constantly plying between Guernsey and London, only to export the crops of the greenhouses.
Nowadays, in order to obtain that same crop of 500 bushels of potatoes, we must plough every year a surface of four acres, plant it, cultivate it, weed, it, and so on; whereas with the glass, even if we shall have to give perhaps, to start with, half a day's work per square yard in order to build the greenhouse—we shall save afterwards at least one-half, and probably three-quarters of the yearly labour required formerly.
These are facts, results which every one can verify himself. And these facts are already a hint as to what man could obtain from the earth if he treated it with intelligence.
V
In all the above we have reasoned upon what already withstood the test of experience. Intensive culture of the fields, irrigated meadows, the hot-house, and finally the kitchen garden under glass are realities. Moreover, the tendency is to extend and to generalize these methods of culture, because they allow of obtaining more produce with less work and with more certainty.