secretion in vegetables, no less than gall and urine are in animals; or that crystals cannot result from the percolation of sap or other liquid through an impermeable, inorganic rock? And these were the very gems of science, when Sir Francis Bacon was a prodigy of learning.

I am aware, that I ought not to waste this opportu nity in quoting nonsense, even, from the highest authority; but I cannot resist the temptation, to present you with a few more specimens from this fountain of literary absurdity, which was, for a long time, esteemed the quintessence of abstract philosophy.

Upon the subject of temperature, my Lord Bacon says, p 270,"'The producing of cold is very worthy the inquisition, both for the use, and disclosure of causes: For heat and cold are Nature's two hands, whereby she chiefly worketh; and heat we have, in readiness, in respect of the fire; but for cold, we must stay till it cometh, or seek it in deep caves, or upon high mountains: And when all is done, we cannot obtain it, in any great degree; for furnaces of fire are far hotter than a summer's sun; but vaults or hills are not much colder than a winter's frost." And of the means of producing cold, "the first is that which Nature presenteth us withal: viz. the expiring of cold out of the inward parts of the earth, in winter, when the sun hath no power to overcome it; the earth being, as hath been said by some, primum frigidum,” or originally cold. "The second cause of cold is the contact of cold bodies; for cold is active and transitive, into bodies adjacent, as well as heat, which is

seen, in those things, that are touched with snow or cold water. The third cause is the primary nature of all tangible bodies; for it is well to be noted, that all things, whatsoever, tangible, are of themselves cold, except they have an accessory heat, by fire, life or motion: For even the spirit of wine, or chemical oils, which are so hot in operation, are to the first touch cold. The fourth cause is the density of the body; for all dense bodies are colder than most other bodies, as metals, stone, glass; and they are longer in heating than softer bodies. And it is certain, that earths dense, tangible hold all the nature of cold. The cause is, for that all matters tangible being cold, it must needs follow, that when the matter is most congregate, the cold is the greater. The fifth cause of cold, or rather of increase and vehemency of cold is a quick spirit, inclosed in a cold body; as will appear to any, that shall attentively consider of nature, in many instances. We see nitre, which hath a quick spirit, is cold, more cold to the tongue, than stone; so water is colder than oil, because it hath a quicker spirit-and snow is colder than water, because it hath more spirit within it. So we see, that salt put to ice, as in the producing of artificial ice, increaseth the activity of cold. So some insects which have spirit of life, as snakes and silkworms, are, to the touch, cold; so quicksilver, (or metallic mercury,) is the coldest of metals, because it is fullest of spirit. The sixth cause of cold is the chasing and driving away of spirits, such as have some degree of heat; for the banishing of the heat must needs leave any body cold.

This we see, in the operation of opium and stupefactives, upon the spirits of living creatures; and it were not amiss, to try opium, by laying it upon the top of a weather-glass, to see whether it will contract the air: But I doubt it will not succeed; for beside that the virtue of opium will hardly penetrate, through such a body as glass, I conceive that opium and the like, make the spirits fly rather by malignity, than by cold." Seventhly and lastly, he says, "the same effect must follow upon the exhaling, or drawing out of the warm spirits, that doth upon the flight of the spirits. There is an opinion, that the moon is magnetical of heat, as the sun is of cold and moisture: It were not amiss, therefore, to try it with warm waters; the one exposed to the beams of the moon; the other with some screen betwixt; and see whether the former will cool sooner."

It should be entirely unnecessary for me to point out, to you, the fallacies of this long quotation. It is altogether impossible, that any of you, for whom this discourse was prepared, shall misapprehend them. You cannot have evaded the conclusion, that this great author was childishly ignorant of the nature of heat, or caloric, and of the laws, by which its phenomena are governed. And are you not equally impressed with the discrepancy and imbecility of his misinterpretations?

You have not forgotten, that his fifth cause of cold is a "spirit, enclosed in a cold body," and that he instances the cold of nitre, or nitrate of potash, commonly called salt-petre, in the process of solution

upon the tongue, in confirmation. How clearly this example illustrates his ignorance of a principle, that chemistry has long since elucidated, viz., that the transformation of a solid, to a liquid, is invariably attended with the reduction of sensible caloric, which seems to have been absorbed and appropriated, as an indispensable constituent of the material, in its state of transformation; and in this state, wherein it is incapable of affecting the thermometer, or of being detected by the touch, it is denominated latent heat; of which, it is little less than discourtesy, that I should say, it must, necessarily, be derived from the surrounding bodies, and, therefore, in the case in question, from the tongue itself, thereby reducing the temperature, and consequently occasioning the sensa tion of cold. Nor can you have overlooked the surprising inconsistency of an immediately subsequent remark, in which he declares the sixth cause of cold to be "the chasing and driving away of spirits, such as have some degree of heat." What a farrago of nonsense have we here. A body cold, from the endowment of a cold spirit-rendered still colder by the abduction of a hot one, between which, there should have been represented an energetic contest for mastery; and this would have afforded a single cause of heat, altogether more plausible and efficient, than any he has propounded for the production of either heat or cold. He seems to have known nothing of the radiation, reflection, or conduction of heat; or his interpretations of cold (which, by the by, is nothing but the negation of heat,) would not have been char

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acterized by an irrecoverable decrepitude, with which, even, crutches are unavailable. Natural Philosophy was certainly in its infancy, when it recognized cold, as one of the active agencies of Nature!

A few moments further encroachment upon your patience will have ended my quotations, for the present.

Of the transmutation of bodies, or the changing of one substance into another, our philosopher says, p 275, "It is very probable, as hath been touched, that that which will turn water into ice, will, likewise, turn air, some degree nearer, into water: Therefore, try the experiment of the artificial turning water into ice, whereof we shall speak, in another place, with air in place of water, and the ice about it. And though it be a greater alteration, to turn air into water, than water into ice, yet there is this hope, that, by continuing the air longer time, the effect will follow."

Lord Bacon's geological notions are quite too absurdly curious to be entirely omitted in these quotations. He says, of the induration of bodies, "The examples, taking them, promiscuously, are many, as the generation of stones within the earth, which, at the first, are but rude earth, or clay; and so minerals, which come, no doubt, at first of juices concrete, which afterwards indurate; also the exudation of rock diamonds and crystal, which harden with time.” "For indurations by cold, there be few trials of it; for we have no strong or intense cold here, on the surface of the earth, so near the beams of the sun and the heavens. The likeliest trial is by snow and