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Fuller, Andrew, Letter III. from
Remarks on the spirit of his third letter
on his arguments
Jonah and the whale
gay young gentleman, lately converted
New Creation, Wesley on
Natural History 1, 41, 81, 121, 161, 201, 241, 281, 321, 361, 401
Prophecy, pretenders to
by a Sussex Fariner answered
Talents, different Application of
St. Pierre's Theory of the
Winchester's Writings published in Holland
we view the surface of our globe, we are stricken with the appearance of those streams of water which we call rivers, which
beautify the prospect, fertilize the soil, and subserve the most - valuable purposes of human life. The study of nature has been the employment of wise men in every age; yet the attainments of human research have never been fully satisfactory to the mind. The greatest philosophers have known only a little, guessed at inore, and lamented their ignorance of most parts of the works of God. • The sun ariseth, and the sun goeth down, and pants for the place whence he arose. All things are full of labour--man cannot utter it. All rivers run into the sea, yet the sea is not full. Unto the place whence the rivers come, thither they return again. The eye is not satisfied with seeing, nor the ear with hearing." Such were the reflections of the wisest of the ancient Jews.
Whence are rivers produced ? whence do they derive those unceasing stores of water, which continually flow in their spacious channels? This question has divided the opinions of mankind almost beyond any other topic in natural history. Almost every philosopher who has thought upon the subject, has given a solution different from others. But in the controversy on this head, we may rank the contending parties chiefly under two great leaders, M. De La Hire, a famous French writer, on the one hand; and the great Dr. Hally on the other. The first contends that rivers must be supplied from the sea, strained through the pores of the carth; the second has endeavoured to demonstrate that the clouds alone are sufficient for the supply. Both sides have called mathematics to their aid ; and, in the opinion of the by-standers, have shewn, that long and laborious calculations can at any time be made, by men of science, to obscure bath sides of a question. VOL. IV.
De La Hire, to slew that the clouds, by rain, are insufficient for the production of rivers, asserts, that raiu never penetrates the surface of thie earth above sixteen inches. Hence he infers, that it is impossible for it, in many cases, to sink so as to be found at such considerable depths below, as to give rise to rivers. He grants, indeed, that rain water is often seen to mix with rivers, and greatly to swell their currents; but that a much greater part of it evaporates. “ If, says he, the whole earth were covered with water, evaporation alone would be sufficient to carry off two feet nine inches of it in a year : and yet we know very well, that hardly nineteen inches of rain water fall in that time; so that evaporation would carry offa inuch greater quantity than is ever known. The small quantity of rain water that falls in a year is therefore but barely sufficient for the purposes of vegetation. Two leaves of a fig-tree have been found, by experiment, to imbibe from the earth, in five hours and a half, two ounces of water. This implies the gre t quantity of fluid that inust be exhausted in the maintenance of one single plant. Add to this, that the waters of the river Rungis do, by calculation, rise to fifty inches, and the whole country from whence these waters are supplied, never receives fifty inches in the year, by rain. Besides this, there are many salısprings, which are known to proceed immediately from the sea, and are subject to its flux and reflux. In short, wherever we dig beneath the surface of the earth, except in a few instances, water is to be found; and it is this subterraneous' water, which is raised into steam, by the internal heat of the earth, that feeds plants. It is this water that distils through the interstices of the earth; and there cooling, forms fountains. It is this subterraneous water also that forms the chief supply of rivers, and pours plenty over the whole earth.” See Hist. de l'Acad 1713. p. 56.
Dr. Hally, on the contrary, asserts, that the vapours which are exhaled from the sea, and driven by the winds upon land, are more than sufficient to supply, not only plants with moisture, but also to furnish a sufficiency of water to furnish the greatest rivers. He procured an estimate to be made of the quantity of water emptied at the mouth of large rivers; and of the quantity also, raised from the sea by evaporation, and it was found, that the latter by far exceeds the former. This calculation was made by Mr. Mariotte. By him it was found, upon receiving such rain as fell in a year, in proper vessel, fitted for that purpose, that, one year with another, there might fall about twenty inches of water upon the surface of the earth throughout Europe. It was also computed, that the river Seine, from its source to the city of Paris, might cover an extent of ground, that would supply it annually with above seven billions of cubic feet of this water, formed by evaporation. But, upon computing the quantity which passed through the arches of its bridges in a year, it was found to amount to only two hundred and eighty millions of cubic feet, which is not above a sixth part of the former number. Hence, therefore, it appears, that this river may receive a supply brought to it by the evaporated waters of the sea, six times greater than what it gives back to the sea by its current: and therefore, evaporation is more than sufficient for maintaining the greatest rivers, and supplying the purposes of vegetation.