A much more recent science than astronomy, the science of chemistry, undertakes to instruct us as to the composition of the universe, and it is marvellous how much it can tell us even of the composition of the stars. What, then, is its most general and certain result? Just this, that order of the strictest kind, the most definite proportions, are wrought into the very structure of every world, and of every compound object in the world, air and water, earth and mineral, plant and animal. The vast variety of visible substances are reducible to rather more than sixty constituent elements, each of which has not only its own peculiar properties but its own definite and unvarying combining proportions with other elements, so that amidst the prodigious number of combinations all is strictly ordered, numerically exact. There is no chemical union possible except when the elements bear to each other a numerically constant ratio. Different compounds are always the products of the combination of the elements in different yet strictly definite proportions, there being no intermediate combinations, no transitional compounds. If each element did not admit of union with many others, the world would be dead and poor, its contents few and unvaried; if their unions were not always regulated by law, disorder would everywhere prevail. How comes it that they are so made in relation to one another that their manifold unions are ever regulated by law, and generate an endless variety of admirable products? Who made them thus? Did they make themselves? or, did any blind force make them? Reason answers that they must have been made by an intelligence which wanted them for its purposes. When the proportions of the elementary constituents are altered, the same elements produce the most diverse substances with the most dissimilar and even opposite properties, charcoal and diamond, a deadly poison or the breath of life, theine or strychnine. These powers all work together for good; but if they worked even a very little differently--if the circumstances in which they work, not to speak of the laws by which they work, were altered--they would spread destruction and death through the universe. The atmosphere is rather a mixture than a combination of chemical elements, but it is a mixture in which the constituents are proportioned to each other in the only way which fits it to sustain the lives of plants and animals, and to accomplish its many other important services; and wonderful in the extreme is the provision made for the constant restoration of the due proportions amidst perpetual oscillations. One of the chiefs of modern chemistry, Baron Liebig, points to what takes place when rain falls on the soil of a field adapted for vegetable growth as to something which "effectually strikes all human wisdom dumb." "During the filtration of rain-water," he says, "through the soil, the earth does not surrender one particle of all the nutritive matter which it