内容简介：
Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: same substance under different modifications or combinations, I shall not inquire. Suffice it to say, that they are found together in the solar beam. Heat is the cause of fluidity, and is essential to the existence of our earth in its present form. The great law of attraction pervades the universe, so far as our observation extends; and had it alone acted, all must have been one solid mass. In order to constitute a system such as ours, it was necessary to introduce a principle of repulsion, which, in a proper degree, should counteract the law of attraction. This principle of repulsion we find in heat; by the action of which solids are converted into fluids, and fluids into vapor. Here we may remark the wisdom displayed in so nicely balancing the principles of attraction and repulsion against each other. Had there been any considerable difference in either of these from what now obtains, the world would not have existed in its present form, nor yielded subsistence to its present inhabitants. Had the power of attraction and cohesion been much greater, and the degree of heat the same as at present, we should have been in want of fluidity: had the quantity of heat been much greater, and attraction, as well as the pressure of the atmosphere, the same as at present, all our fluids would have been converted into vapor. But these powers are exactly adjusted to one another and to the rest of the system. Heat is necessary both to vegetable and animal life; and it appears a decided evidence of the wisdom and goodness of the Supreme Being, that the living functions, both of plants and animals, disengage the portion of heat necessary for their well-being: this they seem to accomplish by converting oxygen into carbonic acid gas, in which process a quantity of heat is evolved. CHAPTER XI...