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hours, as it ordinarily imports: for there is no term in any language that is used with a wider latitude of construction than the Hebrew (jom), or its Arabic form, which is the word for day in the original. We are constantly, indeed, employing this very word, as Englishmen, with no small degree of freedom, in our own age; for you will all allow me to drop the phrase "in our own AGE," and to adopt "in our own DAY" in its stead; thus making AGE and DAY terms of similar import. But in Hebrew the same term is employed, if possible, in a still wider range of interpretation: for it not only denotes, as with ourselves, half a diurnal revolution of the earth, or a whole diurnal revolution, but in many instances an entire year, or revolution of the earth round the sun; and this not only in the prophetic writings, which are often appealed to in support of this remark, but in plain historical narrative as well. Thus in Exod. xiii. 10, the verse, "thou shalt keep this ordinance in its season from year to year," if literally rendered, would be "through days of days," or "through days upon days,”—np'p' D'p'p. And in like manner, Judges xvii. 16, "I will give thee ten shekels of silver by the year," if strictly interpreted, would be "per dies—for the days,” --that is, "for the ANNUAL CIRCLE of days,"-Ò»»»S.
Sometimes, again, the Hebrew Or, or day, comprises the whole term of life, as in 1 Chron. xxix. 15.
Our DAYS (1) on earth are a shadow,
So again, Job xiv. 6.
Turn from him that he may rest,
Till he shall accomplish, as a hireling, his DAY-11".
But the clearest and most pertinent proof of the latitude with which the term, or DAY, is employed in the Hebrew scriptures, is in the very narrative of the creation before us: for after having stated in the first chapter of Genesis that the work of creation occupied a period of SIX DAYS, the same inspired writer, in recapitulating his statement, ch. ii. 4, proceeds to tell us, "these are," or rather, "such were the GENERATIONS of the heavens and of the earth when they were created; IN THE DAY (OV) that the Lord God made the earth and the heavens." In which passage Moses distinctly tells us, that, in the preceding chapter, he has used the term DAY in the sense of generation, succession, or epoch; while we find him here extending the same term DAY to the whole hexaemeron, the entire term of time, whatever it may be, that these six days or generations filled up. So that the sense given to the word by Moses, instead of limiting us to the idea of twenty-four hours' duration, naturally leads us to ascribe, not only a different, but a much enlarged extent of time to the divisions he has marked by the word ', or DAY: or at least to those terms which occurred before the government of the sun and the moon was established, and the heavenly orrery commenced its harmonious action.
Whether, indeed, the days from this last period, constituting the fifth and sixth, were of a different length from any of the preceding, which may also have differed from each other, and were strictly diurnal revolutions of twenty-four hours, it is impossible exactly to determine. But it is a question which by no means affects the actual face of nature or the geological system before us: for as the third or horizontal series of rocks in which petrifactions of KNOWN animal and vegetable substances begin to make their appearance must have continued to augment for ages after the completion of the hexaemeron, or six epochs of creation, whatever
be the duration assigned to them; and as the two loftiest, the fourth and
Thus, in progressive order, uprose the stupendous system of the world: the bright host of morning stars shouted together on its birth-day; and the eternal Creator looked down with complacency on the finished fabric, and saw "that it was good."
* Gen. i. S.
ON ORGANIZED BODIES, AND THE STRUCTURE OF PLANTS COMPARED WITH
THAT OF ANIMALS.
FROM the unorganized world, which has formed the main subject of our two last lectures, let us now rise a step higher in the scale of creation; and ascend from insentient matter to life, under the various modifications it assumes, and the means by which it is upheld and transmitted.
If I dig up a stone, and remove it from one place to another, the stone will suffer no alteration by the change of place; but if I dig up a plant and remove it, the plant will instantly sicken, and perhaps die. What is the cause of this difference? Both have proceeded from a minute molecule, a nucleus or a germ; both have a tendency to preserve their derivative or family configuration, and both have been augmented and perfected from one common soil. If I break the stone to pieces, every individual fragment will be found possessed of the characteristic powers of the aggregate mass; it is only altered in its shape and magnitude; but if I tear off a branch from the plant, the branch will instantly wither, and lose the specific properties of the parent stock.
No external exemination, or reasoning à priori, will explain this difference of effect. It is only by a minute attention to the relative histories, interior structures, and modes of growth of the two substances, that we are enabled to offer any thing like a satisfactory answer; and by such examination we find that the stone has been produced fortuitously, has grown by external accretion, and can only be destroyed by mechanical or chemical force; while the plant has been produced by generation, has grown by nutrition, and been destroyed by death: that it has been actuated by an internal power, and possessed of parts mutually dependent and contributory to each other's functions.
In what this internal power consists we know not. Differently modified, we meet with it in both plants and animals; and wherever we find it we denominate it the principle of life, and distinguish the individual substance - it actuates by the name of an organized being. And hence, all the various bodies in nature arrange themselves under the two divisions of organized and unorganized; the former possessing an origin by generation, growth by nutrition, and a termination by death; and the latter a fortuitous origin, external growth, and a termination by chemical or mechanical force.
This distinction is clear, and it forms a boundary that does not seem to be broken in upon by a single exception. In what, indeed, that wonderful power of crystallization consists, or by what means it operates, which gives a definite and geometrical figure to the nucleus or primary molecule of every distinct species of crystal; and which, with an accuracy that laughs at all human precision, continues to impress the same figure upon the growing crystal through every stage of its enlargement, thus naturally separating one species from another, and enabling us to discriminate each by its geometrical shape alone-we know not: but even here, where we meet with an approach towards that formative effort, that internal action and consent of parts which peculiarly characterize the living substance, there is not the smallest trace of an organized arrangement; while the origin is clearly fortuitous, and the growth altogether external, from the mere apposition of surrounding matter.
So, on the other hand, in corals, sponges, and fuci, which form the lowest natural orders among animals and vegetables, and the first of which seems to constitute the link that connects the animal and vegetable with the mineral world, for it has in different periods been ascribed to each,— simple as is their structure, and obtuse as is the living principle that actuates them, we have still sufficient marks of an organized make; of an origin by generation, the generation of buds or bulbs, of growth by nutrition, and of termination by death.
But the animal world differs from the vegetable as widely as both these differ from the mineral. How are we to distinguish the organization of animals from that of plants?-In what does their difference consist? And here I am obliged to confess, that the boundary is by no means so clearly marked out; and that we are for the most part compelled to characterize the difference rather by description than by definition. Nothing, indeed, is easier than to distinguish animals and vegetables in their more perfect states: we can make no mistake between a horse and a horse-chesnut tree, a butterfly and a blade of grass. We behold the plant confined to a particular spot, deriving the whole of its nutriment from such spot, and affording no mark either of consciousness or sensation; we behold the animal, on the contrary, capable of moving at pleasure from one place to another, and exhibiting not only marks of consciousness and sensation, but often of a very high degree of intelligence as well. Yet, if we hence lay down. consciousness or sensation, and locomotion, as the two characteristic features of animal life, we shall soon find our definition untenable; for while the Linnéan class of worms affords instances, in perhaps every one of its orders, of animals destitute of locomotion, and evincing no mark of consciousness or sensation, there are various species of plants that are strictly locomotive, and that discover a much nearer approach to a sensitive faculty.
However striking, therefore, the distinctions between animal and vegetable life, in their more perfect and elaborate forms, as we approach the contiguous extremities of the two kingdoms we find these distinctions fading away so gradually,
Shade, unperceived, so softening into shade,
and the mutual advances so close and intimate, that it becomes a task of no common difficulty, to draw a line of distinction between them, or to determine to which of them an individual may belong. And it is probable, that that extraordinary order of beings called zoophytes, or animated plants, as the term imports, and which by Woodward and Beaumont were arranged as minerals,* and by Ray and Lister as vegetables, have at last obtained an introduction into the animal kingdom,† less on account of any other property they possess, than of their affording, on being burnt, an ammoniacal smell like that which issues from burnt bones, or any other animal organs, and which is seldom or never observed from burnt vegetable substances of a decided and unquestionable character. Ammonia, however, upon destructive distillation, is met with in small quantities in particular parts of most if not of all vegetables, though never perhaps in the whole plant. Thus it occurs slightly in the wood or vegetable fibre; in
* Phil. Trans. xiii. 277.
↑ Parkinson's Organic Remains, i. 23. ii. 157, 158.
extract, gum-mucilage, camphor, resin, and balsam; gum-resin, gluten, and caoutchouc besides those substances that are common to both animals and vegetables, as sugar, fixed oil, albumen, fibrine, and gelatine. There are some plants, however, that even in their open exposure to a burning heat, give forth an ammoniacal smell closely approaching to that of animal substance. The clavarias or club-tops, and many other funguses, do this. But a distinction in the degree of odour may even here be observed, if accurately attended to. Yet the clavarias were once regarded as zoophytes, and are arranged by Millar in the same division as the corals and coral-lines.*
M. de Mirbel, in his very excellent treatise "On the Anatomy and Physiology of Plants," has endeavoured to lay down a distinction between the animal and the vegetable world in the following terms, and it is a distinction which seems to be approved by Sir Edward Smith: "Plants alone have a power of drawing nourishment from inorganic matter, mere earths, salts, or airs; substances incapable of nourishing animals, which only feed on what is or has been organized matter, either of a vegetable or animal nature. So that it should seem to be the office of vegetable life alone to transform dead matter into organized living bodies." Whence another learned French physiologist, M. Richerand, has observed that the aliments by which animals are nourished are selected from vegetable or animal substances alone; the elements of the mineral kingdom being too heterogeneous to the nature of animals to be converted into their own substance without being first elaborated by vegetable life; whence plants, says M. Richerand, may be considered as the laboratory in which nature prepares aliments for animals.‡
I concur with these elegant writers in admitting the beautiful and harmonious relation so obviously established between minerals, plants, and animals; but it is at the same time impossible to allow of the distinction between vegetable and animal life here laid down; because, first, vegetables are by no means nourished exclusively, as indeed M. Mirbil himself frankly allows, from terrene elements: and secondly, because animals are as little nourished exclusively from vegetable materials. Among insects, worms, and even fishes, there are many tribes that derive by far the greater portion of their increase from the mineral kingdom alone; while even in man himself, air, water, common salt, and lime, which last is almost always an ingredient of common salt, are substances indispensable to his growth, and are derived immediately from the mineral kingdom.
In laying down, therefore, a distinctive character for animals and plants, we are compelled to derive it from the more perfect of each kind and to
* Several species of this genus of fungi have very singular properties: thus, the c. hamatodes has so near a resemblance to tanned leather, though somewhat thinner and softer, as to be named oak-leather club-top, from its being chiefly found in the clefts and hollows of oak-trees. In Ireland, it is employed as leather to dress wounds with; and, in Virginia, to spread plasters upon.
There are some cryptogamic plants, and especially among the mosses, that can be hardly made to burn by any means. Such is the fontinella antipyretica, so called on this very account; and which is hence in common use among the Scandinavians, as a lining for their chimney-sides, and the inside of their chimneys, by way of preservation. So that here we have an approach to mineral instead of to animal substances, and especially to the asbestos and other species of talcose earths. There is one species of byssus, another curious genus of mosses, that takes the specific name of asbestos, from this very property. It is found in the Swedish copper mines of Westmann-land in large quantities; and when exposed to a red heat, instead of being consumed, is vitrified.
†Traite d'Anatomie et de Physiologie vegetale. i. 19. Elemens de Physiologie, &c. cap de la Digestion.