Speaking generally, the chemical composi tion of inorganic objects may be stated to be the more simple, many of them consisting of a single element only, and when more com pound generally presenting binary, and at most ternary combinations of known elements. Organized bodies, on the other hand, are never made up of single elements, they are not even binary combinations, vegetables in the aggre gate being at least ternary, and animals at least quaternary compounds. Though the elements which compose inanimate objects, therefore, are more numerous, the combinations they enter into are less complex than those they form in the constitution of living things.
Another difference in the chemical consti tution of unorganized and of organized bodies consists in the mode or, jbrm in which the che mical elements exist in each. In the former they present themselves immediately as it were, the chemist in his analyses coming upon them at once; in the latter they occur under two forms, the one immediate as in minerals, the other mediate, or arranged under a variety of new and peculiar shapes, which, with reference to the bodies they mainly constitute, are con veniently and fairly spoken of as elements, with the prefix organic, they being exclusively the products of life and organization ; these are also frequently spoken of as the immediate principles of vegetables and animals.
In the inorganic world, again, the con stituent elements of bodies are always united by virtue of, and in harmony with, the general laws of chemical affinity, whilst in the organic the compounds formed are very often even the opposites of those that would have been originated under the dominion of these laws. From this it comes that, whilst the chemist finds almost as little difficulty in recomposing as in disintegrating inorganic objects, he has hitherto failed in compounding any one of the higher organic products or immediate prin ciples of plants and animals.* Chemical analysis we may therefore imagine to be a process of a very different nature as applied to inorganic objects from what it is when ap plied to organic substances. With reference to the former it signifies a simple disintegra tion, with an inherent capacity in the elements separated to reunite into the compound ana lysed ; in the latter it constantly implies de struction, without any such continuing power of recombination among the constituent ele ments. Chemical synthesis, consequently, is an expression that can only be logically used in connection with inorganic. objects.
Considered with reference to their intimate texture, organized beings are no less strikingly different from unorganized bodies. The last are either solid, or fluid, or gaseous ; they never occur commingled, each subserving the ex istence of the other. The water of crystalli zation, and the globules of this and other fluids occasionally found included within the sub stance of minerals, are but adventitious, being' in the first instance entangled among their component molecules, in the second imprisoned within accidental cavities in their substances but contributing in nowise to the existence or duration of the matter that surrounds them.
Organized bodies, on the other hand, consist uniformly of solid and of fluid parts : whilst the vegetable has its woody fibre and constituent parenchyma, it has its sap also ; and animals with their firmer bones, muscles, cellular sub stance, &c. have likewise blood circulating through their bodies, or various fluids de posited within their tissues, which are just as essential to their constitution and continuance as the containing parts themselves. It is even by the mutual play of the solids and fluids which enter into the composition of organized beings that they manifest themselves in action or exhibit the phenomena which are peculiar to them, and which we denominate vital. It were indifferent whether we took away the solids (were such a thing possible) or the fluids of a vegetable or an animal ; in either case it must perish. The solids and fluids of organized beings consequently are in intimate and inseparable relationship one with another.
Consistence.—From this admixture of solids and fluids in the world of organization results the variety of consistence which its objects pre sent. In the inorganic kingdom, rigidity, rigidity, too, which is uniform,—is one of the distinguishing characteristics. In the organic, on the contrary, pliancy and softness, which vary as well in every individual as in almost every part of the same individual, are no less strongly marked and inherent features. So lidity or hardness may be looked upon as the term of perfection of a mineral ; softness, on the other hand, often appears to be the term of perfection among vegetables and animals, the parts in these being generally softer in proportion as they have more important or noble offices to perform. The tender fibrils of the root, the leaves, flowers, stamina and pistilla in plants ; the brain, vessels, viscera, &c. in animals, are softer than the bark and woody fibre, than the bones, ligaments, skin, &c. which form, as it were, but the frame and covering of the proper fabric. This quality also varies in the organic world according to the age of the in dividual : the nearer any organized being is to its birth or origin, the softer will it generally be found to be ; the longer it has lived, the harder will it as uniformly be ascertained to have become. Many organized beings, indeed, in the first stages of their existence, are wholly fluid ; they only acquire consistence as they are evolved and approach maturity.