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may be distinguished from the other orders
of beings. On this principle, however, oys-
ters, muscles, cockles, &c. would be almost
excluded from the class of animals, inas-
much as they usually adhere, or grow to
rocks, &c. and yet it is certain that these
creatures are real animals. But loco-motion
alone is not sufficient to constitute the
generic difference of animals; nor, indeed,
does it sufficiently distinguish an animal
from a plant. Many instances are produced
in which plants manifest loco-motive power.
This is the case with those denominated
sensitive plants, many of which, upon the
slightest touch, shrink back and fold up
their leaves; as the snail in the slightest
touch retires into its shell. There are
some, on which if a fly perches, instantly
close and crush the insect to death. Plants
also change their position and form in differ-
ent circumstances and seasons; they take
advantage of good weather, and guard them-
selves against bad weather; they open their
leaves and flowers in the day, and close
them at night; some close before sun-set,
and some after; some open to receive rain,
and some close to avoid it; some follow the
sun, and some turn from it; the leaves of
some plants are in constant motion during
the day, and at night they sink to a kind of
rest or sleep. It has also been observed,
that a plant has a power of directing its
roots for procuring food; and that it has a
faculty of recovering its natural position
after it has been forced from it. A hop-
plant, for instance, in twisting round a pole,
directs its course from south to west, as the
sun does; if it be tied in the opposite direc-
tion it dies; but if it be left loose in this
direction, it will regain its natural course in
a single night. A honey-suckle proceeds in
a certain direction, till it be too long to
sustain itself; it then acquires strength by
shooting into a spiral form; and if it meet
with another plant of the same kind, both
these coalesce for mutual support, one twist-
ing to the right and the other to the left.
There are other instances in which plants
manifest a faculty of loco-motion; and, per-
haps, in almost as eminent a degree as some
animals. Muscles, e. g. are fixed to one
place as much as plants, nor have they any
power of motion, besides that of opening
and shutting their shells; nor do they seem,
in this respect, to have any superiority, with
regard to the powers of motion, to the sen-
sitive plant and others of a similar kind.
In order, therefore, to form a complete and
satisfactory distinction between animals and

vegetables, as well as minerals, it is neces-
sary to combine with spontaneous loco-
motion, which they unquestionably possess
in a more perfect degree than plants, the
powers of sensation. These seem to be un-
exceptionably distinguishing and characteris-
tic. However, M. Buffon, after allowing
that although progressive motion constitute
a perceptible difference between an animal
and a vegetable, this distinction is neither
general or essential; proceeds to state, that
sensation more essentially distinguishes ani-
mals from vegetables. But he adds, that
this distinction is neither sufficiently general
nor decided. If sensation, he says, implied
no more than motion consequent upon a
stroke or impulse, the sensitive plant enjoys
this power; whereas, if by sensation we
mean the faculty of perceiving, and of com-
paring ideas, it is uncertain whether brute
animals are endowed with this faculty. If
it should be allowed to dogs, elephants, &c.
whose actions seem to proceed from motives
similar to those by which men are actuated,
it must be denied to many species of animals,
particularly to those that appear not to pos-
sess the faculty of progressive motion. If
the sensation of an oyster, e. g. differ in de-
gree only from that of a dog, why do we not
ascribe the same sensation to vegetables,
though in a degree still inferior? In examin-
ing the distinction which arises from the
manner of feeding, he observes, that animals
have organs of apprehension, by which they
lay hold of their food: they search for pas-
ture, and have a choice in their aliment.
But, it is alleged, that plants are under the
necessity of receiving such nourishment as
the soil affords them, without exerting any
choice in the species of their food, or in the
manner of acquiring it. However, if we
attend to the organization and action of the
roots and leaves, we shall soon be convinced
that these are the external organs by which
vegetables are enabled to extract their food;
that the roots turn aside from a vein of
bad earth, or from any obstacle which they
meet with in search of a better soil; and
that they split and separate their fibres in
different directions, and even change their
form, in order to procure nourishment to
the plant. From this investigation, he con-
cludes that there is no absolute and essential
distinction between the animal and veget-
able kingdoms; but that nature proceeds
by imperceptible degrees, from the most
perfect to the most imperfect animal, and
from that to the vegetable; and that the
fresh water polypus may be regarded as the

last of animals, and the first of plants. After examining the distinctions, this author proceeds to state the resemblances which take place between animals and vegetables. The power of reproduction, he says, is common to the two kingdoms, and is an analogy both universal and essential. A second resemblance may be derived from the expansion of their parts, which is likewise a common property, for vegetables grow as well as animals; and though some difference in the manner of expansion may be remarked, it is neither general nor essential. A third resemblance results from the manner of their propagation. Some animals are propagated in the same manner, and by the same means as vegetables. The multiplication of the sacceron, or vine-fritter, which is effected without copulation, is similar to that of plants by seed; and the multiplication of the polypus by cuttings resembles that of plants by slips. Hence it is inferred that animals and vegetables are beings of the same order, and that nature passes from the one to the other by imperceptible degrees; since the properties in which they resemble one another, are universal and essential; while those by which they are distinguish ed, are limited and partial. Dr. Watson, Bishop of Llandaff, has examined, with his usual judgment, the distinguishing marks between animals and vegetables. He rejects, as insufficient, both figure and spontaneous motion; and if perception be substituted in their stead, it will be found to be a criterion that is, in many respects, liable to exceptions. However, the ingenious and learned prelate produces many chemical, physical, and metaphysical reasons, which serve to render the supposition not altogether indefensible, that vegetables are endowed with the faculty of perception. Dr. Percival, likewise, in a paper read before the Literary and Philosophical Society of Manchester, produces several arguments to evince the perceptive power of vegetables. From the reasoning adduced by both these ingenious writers, of which a more particular account will be given in the sequel of this work (see PLANTS and VEGETABLES); those who duly advert to it, will, we conceive, incline to the opinion that plants are not altogether destitute of perception. But on a question that has perplexed and divided the most ingenious and inquisitive naturalists, it is very difficult to decide. If we extend to the vegetable kingdom that kind of vitality with which sensation and enjoyment are connected, there will remain no discernible

boundary between this and the animal king dom; and that which has been considered as the distinctive characteristic of animals, and by which they are separated from vegetables, will be abolished. We shall now add, that the principle of self-preservation belongs to all animals; and it has been argued that this principle is the true characteristic of animal life, and that it is unquestionably a consequence of sensation. There is no animal, when apprehensive of danger, that does not put itself into a posture of defence. A muscle, when it is touched, immediately shuts its shell; and as this action puts it into a state of defence, it is ascribed to a principle of self-preservation. Those who adopt this reasoning, allege that vegetables do not manifest this principle. When the sensitive plant, for instance, contracts from a touch, it is no more in a state of defence than before, for whatever would have destroyed it in its expanded state, will also destroy it in its contracted state. They add, that the motion of the sensitive plant proceeds only from a certain property called irritability; and which, though possessed by our bodies in an eminent degree, is a characteristic neither of animal or vegetable life, but belongs to us in common with brute-matter. The sensitive plant, after it has contracted, will suffer itself to be cut in pieces, without making the least effort to escape. This is not the case with the meanest animal. An hedge-hog, when alarmed, draws its body together, and expands its prickles, thus putting itself in a posture of defence: when thrown into the water, the same principle of self-preservation prompts it to expand its body and swim. A snail, when touched, withdraws itself into its shell; but if a little quick-lime be sprinkled upon it, so that its shell is no longer a place of safety, it is thrown into agonies, and endeavours to avail itself of its loco-motive power, in order to escape that danger. Muscles and oysters also, though they have not the power of progressive motion, constantly use the means which nature has given them for self-preservation. We, ourselves, possess both the animal and vegetable life, and ought to know whether there be any connection between vegetation and sensation, or not. We are conscious that we exist, that we hear, see, &c. but of our vegetation we are absolutely unconscious. We feel a pleasure in gratifying the demands of hunger and thirst; but we are totally ignorant of the process by which our aliment is formed into chyle, the chyle mixed with

the blood, the circulation of that fluid, and the separation of all the humours from it. If we, then, who are more perfect than other vegetables, are utterly insensible of our own vegetable life, why should we imagine that the less perfect vegetables are sensible of it? We have within ourselves a demonstration that vegetable life acts without knowing what it does; and if vegetables are ignorant of their most sagacious actions, why should we suppose that they have any sensation of their inferior ones; such as contracting from a touch, turning towards the sun, or advancing to a pole? As to that power of irritability which is observed in some plants, our solids have it when deprived both of animal and vegetable life; for a muscle, cut out of a living body, will continue to contract, if it be irritated by pricking, after it has neither sensation nor vegetation. Encycl. Brit. On the other hand, those who are of opinion that plants possess powers of perception, allege that their hypotheses recommends itself by its consonance to those higher analogies of nature, which lead us to conclude that the greatest possible sum of happiness exists in the universe. The bottom of the ocean is overspread with plants of the most luxuriant magnitude; and immense regions of the earth are overspread with perennial forests. Nor are the Alps or the Andes destitute of herbage, though buried in depths of snow: and can it be imagined that such profusion of life subsists without the least sensation or enjoyment? Let us rather, with humble reverence, suppose that vegetables participate, in some low degree, of the common allotment of vitality; and that one great Creator hath appointed good to all living things, in number, weight, and measure.

ANIMAL flower, a name given to a variety of creatures of the Vermes tribe, that bear some resemblance to a flower. These, for the most part, belong to the order Molluscæ; the name is, however, frequently given to a different order, viz. the Zoophytes.

ANIMAL manures, in agriculture, are all substances that are formed from the decomposition of animal substances of any kind; as the muscles, blood, hair, wool, bones, fat, &c. These are generally esteemed as more powerful, in promoting vegetation, than such as are derived from vegetable matters. On account, however, of their being but seldom procured in large quantities, they are generally made use of in the state of mixture or combination with other materi

als. By the action of ammonia, which is constantly formed during the decomposition of animal substances, the mould is made more suitable for plants.

ANIMAL, parts of, substances which compose the bodies of animals may be arranged under the following heads:

1. Bones and shells 2. Horns and nails 3. Muscles

4. Skin

5. Membranes

6. Tendons and ligaments

7. Glands

8. Brain and nerves

9. Hair and feathers

10. Silk and similar bodies.

Besides these substances which constitute the solid part of the bodies of animals, there are a number of fluids, the most important of which is the blood, which pervades every part of the system in all the larger animals: the rest are known by the name of secretions, because they are formed or secreted, as the anatomists term it, from the blood. The principal animal secretions are the following:

1. Milk

2. Eggs 3. Saliva

4. Pancreatic juice 5. Bile

6. Cerumen 7. Tears

8. Liquor of the pericardium 9. Humours of the eye 10. Mucus of the nose, &c. 11. Sinovia

12. Semen

13. Liquor of the amnios

14. Poisonous secretions.

from the blood or the food, on purpose to Various substances are separated either be afterwards thrown out of the body as useless or hurtful. These are called excretions. The most important of them are, 1. Urine

2. Fæces.

Besides the liquids which are secreted for the different purposes of healthy animals, there are others which make their appearance only during disease, and which may therefore be called morbid secretions. The most important of these are the following: 1. Pus

2. The liquor of dropsy
3. The liquor of blisters.

To these we must add several solid bodies, which are occasionally formed in different cavities, in consequence of the deceased action of the parts. They may be called morbid concretions. The most remarkable of them are the following:

1. Salivary calculi

2. Concretions in the lungs, liver, brain, &c.

3. Intestinal calculi
4. Biliary calculi
5. Urinary calculi
6. Gouty calculi.

ANIMAL substances, or those which have hitherto been detected in the animal kingdom, and of which the differem parts of animals, as far as these have been analysed, are found to be composed, may be arranged under the following heads:

1. Gelatine 2. Albumen

3. Mucus

4. Fibrin

5. Urea

6. Saccharine matter 7. Oils

8. Resins

9. Sulphur

10. Phosphorus

11. Acids

12. Alkalies

13. Earths

14. Metals.

See the several articles in their alphabetical order.

ANIMAL, functions of. See ASSIMILAtion, Digestion, Perspiration, RESPIRATION, &c.

ANIMALS, generation of. See the article GENERATION.

ANIMALS in heraldry, are much used, both as bearings and supporters. It is to be observed, that in blazoning animals must be interpreted in the best sense, and so as to redound to the greatest honour of the bearers. For example, the fox being renowned for wit, and likewise given to filching for his prey; if this be the charge of an escutcheon, we must conceive the quality represented to be his wit, and not his theft. All beasts must be figured in their most noble action; as a lion rampant, a leopard or wolf passant, a horse running or vaulting, a greyhound coursing, a deer tripping, and a lamb going with a smooth pace. In iike manner, every animal must be moving and looking to the right side of the shield, the right foot being

placed foremost. These are the precepts given by Guillim, and yet we find that there are lions passant, couchant, and dormant, as well as rampant.

ANIMALCULE, an animal so minute in its size, as not to be the immediate object of our senses.

Animalcules are usually divided into two distinct sections, visible, and microsopical. The first, though visible, cannot be accurately discerned without the help of glasses: the second are discoverable only by the, microscope. Some have supposed there are others invisible. The existence of these cannot well be disputed, though it cannot be asserted, unless we conclude, that the microscope has not yet arrived at its highest degree of perfection. Reason and analogy give some support to the conjectures of naturalists in this respect: animalcules are discerned of various sizes, from those which are visible to the naked eye, to such as appear only like moving points under the microscopic lenses of the greatest powers; and it is not unreasonable to imagine, there. fore, that there are others which may still resist the action of the microscope, as the fixed stars do that of the telescope, with the greatest powers hitherto invented.

Animalcules, visible; amongst these are included an amazing variety of creatures, by no means of analagous natures. Those numerous creatures which crowd the water. in the summer months, changing it sometimes of a deep or pale red colour, green, yellow, &c. are of this description. The large kinds are chiefly of the insect, or vermes tribes, and of which the monoculus pulex is particularly remarkable, being sometimes found in such abundance, as to change the water apparently to a deep red. A símilar appearance is likewise occasioned by the circaria mutabilis, when it varies in colour from green to red; vorticella fasciculata also changes it to green; and rotatoria to yellow. To this section we must also refer many of the acarus and hydrachna genera, and a multitude of other creatures that will be noticed hereafter.

Animalcules, microscopical. The microscope discovers legions of animalcules in most liquors, as water, vinegar, beer, dew, &c. They are also found in rain and several chalybeate waters, and in infusions of both animal and vegetable substances, as the seminal fluids of animals, pepper, oats, wheat and other grain, tea, &c. &c. The conteinplation of animalcules has made the ideas of infinitely small bodies extremely familiar to

ANIMALCULE.

us. A mite was anciently thought the limit but we are not now surprised of littleness; to be told of animals twenty-seven millions of times smaller than a mite. Minute animals are found proportionably much stronger, more active and vivacious than large ones. The spring of a flea in its leap, how vastly does it outstrip any thing greater animals are capable of! A mite, how vastly faster does it run than a race-horse! M. de l'Isle has given the computation of the velocity of a little creature scarcely visible by its smallness; which he found to run three inches in half a second: supposing now its feet to be the fifteenth part of a line, it must make five hundred steps in the space of three inches; that is, it must shift its legs five hundred times in a second, or in the ordinary pulsation of an artery. The excessive minuteness of microscopical animalcules conceals them from the human eye. One of the wonders of modern philosophy is, to have invented means for bringing creatures to us so imperceptible under our cognizance and inspection: an object a thousand times too little to be able to affect our sense should seem to have been very safe. Yet we have extended our views over animals, to whom these would be mountains. In reality, most of our microscopical animalcules are of so small a magnitude, that through a lens, whose focal distance is the tenth parth of an inch, they only appear as so many points; that is, their parts cannot be distinguished, so that they appear from the vertex of that lens under an angle not exceeding a minute. If we investigate the magnitude of such an object, it will be found nearly equal too of an inch long. Supposing, therefore, these animalcules of a cubic figure, that is of the same length, breadth, and thickness, their magnitude would be expressed by the cube of the fraction To that is, by the number is, so many parts of a cubic inch, is each animalcule equal to. Leeuwenhoeck calculates, that a thousand millions of animalcula, which are discovered in common water, are not altogether so large as a grain of sand. This author, upon examining the male sperm of various animals, discovered in many infinite numbers of animalcula not larger than those above mentioned. In the milt of a single cod fish there are more animals than the whole earth; for a grain there are upon of sand is bigger than four millions of them. The white matter that sticks to the teeth also abounds with animalcules of various fi

27 1000,000,000,000,000,

that

gures, to whichr vinegar is fatal; and it is
known, that vinegar contains animalcules in
the shape of eels. In short, according to
this author, there is scarcely any thing which
corrupts without producing animalcules.
Animalcules are said to be the cause of va-
a disorder arising from the irritation of
rious disorders. The itch is known to be
a species of animalcula found in the pus-
tules of that ailment: when the commu-
nication of it by contact from one to an-
other is easily conceived, as also the reason
of the cure being effected by cutaneous ap-
plications. In the Philosophical Transac-
tions, vol. lix., is a curious account of the
animalcules produced from an infusion of
potatoes, and another of hemp-seed, by the
late Mr. Ellis." "On the 25th of May, 1768,
tatoe in the New River water, till it was re-
Fahrenheit's thermometer 70°, I boiled a po-
duced to a mealy consistence. I put part
of it, with an equal proportion of the boil-
ing liquor, into a cylindrical glass vessel,
that held something less than half a wine-
a glass cover. At the same time I sliced
pint, and covered it close immediately with
an unboiled potatoe, and, as near as I could
judge, put the same quantity into a glass
vessel of the same kind, with the same pro-
and covered with a glass cover, and placed
portion of New River water not boiled;
both vessels close to each other." "On the
26th of May, 24 hours afterwards, I exa-
mined a small drop of each by the first mag-
nifier of Wilson's microscope, whose focal
distance is reckoned at part of an inch;
of animalcula, of a linear shape, very distin-
and, to my amazement, they were both full
lerity, so that there appeared to be more
guishable, moving to and fro with great ce-
each drop." "This experiment I have re-
particles of animal than vegetable life in
ceed in proportion to the heat of the cir-
peatedly tried, and always found it to suc
cumambient air; so that even in winter, if
the liquors are kept properly warm, at least
in two or three days the experiment will
ferent seeds-men in different parts of the
succeed." "I procured hemp-seed from dif-

town.

Some of it I put into the New River water, some into distilled water, and some into very hard pump-water. The result was, that in proportion to the heat of the weather, or warmth in which they were minute animalcula in all the infusions; and, kept, there was an appearance of millions of some time after, oval ones made their áppearance. These were much larger than the first, which still continued: these wrig

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