In the thick the Hoe-plough went deeper, and consequently raised more Pasture there; but then it went the shallower in the thin; and when the Land became of a more equal Depth the Fifth Year, the Plough and the Hoe-plough went deeper, all the Piece being taken together; for the Crop could be but in proportion to the different Pasture, allowing somewhat for the more or less Seasonableness of the Year. The Soil, in this our Case, cannot be supplied in Substance, but from the Atmosphere. The Earth which the Rain brings can do it alone, if it fall in great Quantity; for by Water, ’tis plain, the Earth which nourished _Helmont_’s Tree was supplied; for the Tin-cover of the Box wherein it stood, prevented the Dews from entering. Dews must add very much to the Land, thus continually tilled and hoed; for they are more heavily charged with terrestrial Matter than Rain is, which appears from their forcing a Descent through the Air, when ’tis strong enough to buoy up the Clouds from falling into Rain: And Dew, when kept in a Vessel long enough to putrefy, leaves a greater Quantity of black Matter at the Bottom of the Vessel, than Rain-water does in a Vessel of the same Bigness, filled with it till putrefied. Dews at Land, I suppose, are first exhaled from Rivers, and moist Lands, and from the Expirations of Vegetables; most of the Dew which falls on it is exhaled from untilled Land; but most of that which falls on well tilled or well hoed Land, remains therein unexhaled; so that the untilled Ground helps, by that means, to enrich and augment the tilled: For if an Acre be tilled for Two Years together without sowing, it will become richer by that Tillage, than by lying unplowed Four Years, which may be easily proved by Experience[142]. [142] _Non igitur Fatigatione, quemadmodum plurimi crediderunt_, nec Senio, _sed nostra scilicet_ Inertia, _minus benigne nobis Arva respondent._ Colum. _lib._ xi. _cap._ 1. But then, as to Rain, the Sea being larger than all the Land (and its Waters, by their Motion, becoming replete with terrestrial Matter), ’tis not unlikely, that more Vapour is raised from One Acre of Sea, than from One hundred Acres of Land. Some have been so curious as to compute the Quantity of Rain, that falls yearly in some Places in _England_, by a Contrivance of a Vessel to receive it; and ’tis found, in one of the driest Places, far from the Sea, to be Fourteen Inches deep, in the Compass of a Year; in some Places much more; _viz._ at _Paris_, Nineteen Inches; in _Lancashire_, Mr. _Townley_ found, by a long-continued Series of Observations, that there falls above Forty Inches of Water in a Year’s time. Could we as easily compute the true Quantity of Earth in Rain-water, as the Quantity of Water is computed, we might perhaps find it to answer the Quantity of Earth taken off from our hoed Soil annually by the Wheat.