of the nasal cavities, are distributed the delicate ramifications
of the olfactory nerves, or the nerves of smell. These nerves are
constructed for transmitting to the mind impressions arising from
the floating exhalations of odoriferous substances. It is through
these nasal cavities, principally, that man and quadrupeds breathe;
hence the respiration of the air informs us of our proximity to
objects disgusting and noxious, or, on the contrary, attractive from
their fragrance. Surely we need not adduce instances in proof of our
position. The scent of putrescent animal or vegetable matters is
in itself a warning to us to retire from the locality of mortific
corruption, and escape from the region of disease. How loathsome
to our sense are these putrescent effluvia! They nauseate us even
to sickness--nay, sometimes almost to fainting; indeed, the writer
has seen a violent fit of epilepsy produced by the overpowering and
horribly disgusting odour of the matter contained in the scent pouch
of a small quadruped, the grison, (_Galictis vittata_,) which he was
dissecting, the sufferer being a practical zoologist, accustomed to the
dissecting-room.
But when the voice of the nightingale is heard, and the air is loaded
with the perfume of the hawthorn blossom, and of thousands of spring
flowers, are we not invited, as it were by a secret call, to walk
abroad through woodlands and meadows, contemplating the works of God?
We are thus lured to beneficial exercise--to inhale
"The breezy fragrance of the morn"--
to forget the trials of life, and muse upon a still brighter world,
where the flowers perish not, where storms come not, and where winter
is unknown. Thus, to our bodily health do our senses administer; and
thus the sense of smell calls us from the close room of the populous
city, into the fresh air of the country--from the crowded town,
"Where houses thick and sewers annoy the air,"
to issue forth on a summer's morn, and breathe the pure air redolent of
sweetest odours.
When overpoweringly offensive effluvia disgust us, we endeavour to stop
our breath--we breathe at protracted intervals, take in as little air
as possible, and endeavour to escape from the infected locality; but
do we flee away from the gale bearing the scent of the honey-suckle,
the bean-field, or the new-mown hay? It is, indeed, rather to our
pleasures, to our mental enjoyment, to our delight, or to our disgust
and abhorrence, that our sense of smell administers. We depend little
upon it for our discrimination between things acting as poison,
and things nutritious or wholesome. How pleasant is the smell of
laurel-water or prussic acid--how dull and insipid the smell of wheaten
flour! We must not, then, always be guided by our sense of smell,
although in general it serves us as a monitor.
The sense of smell is intimately combined with that of taste; indeed,
it is a powerful auxiliary to it, for, as a learned writer well
observes, "taste, without the aid of smell, would be very vague in its
indications, and limited in its range." Nevertheless, savage people,
in whom the sense of smell is far more acute than in civilized races,
do not appear to possess a greater refinement of taste--indeed, what
the former regard as delicacies would be rejected by the latter with
abhorrence. Most quadrupeds possess the sense of smell in far greater
perfection than man, and are evidently influenced by it in their choice
or rejection of food. In the carnivorous tribes this sense is, perhaps,
at its highest ratio, and many pursue their prey guided by their
olfactory organs alone.
Certain odours are agreeable to some few animals, irrespective of
food; but on this point our range of information is limited. The cat
delights in the scent of valerian, and some other herbs, although they
are not among the articles of this animal's diet; yet to the cat and
the dog, the odour of the sweetest flowers yields no pleasure. Birds,
in general, are endowed with the sense of smell in a far lower degree
than quadrupeds, and the olfactory organs are far less developed.
Birds of prey are guided by their keen powers of vision, and, indeed,
if we are to trust to the experiments of Audubon, the sense of smell
even in the carrion-loving vulture, contrary to the opinion of the
ancients, as well as of modern naturalists, is at a low ratio; for, as
he asserts, the stuffed skin of an animal will attract a vulture from
its "pride of place," in the upper regions of the air. It is true that
this assertion has been contradicted by Mr. Waterton, but it is again
confirmed by the experiments and observations of Mr. Bachman, which
are recorded in Loudon's Magazine of Natural History, viii. 167; and
M. Levuillant seems to have considered that it is by the eye chiefly,
if not exclusively, that the vulture obtains its disgusting food. The
following observations from the proceedings of the Zoological Society
will be here, perhaps, not unacceptable:--
March 14th, 1837.--"A paper was read on the habits of the _Vultur
Aura_, by Mr. W. Sells, with notes of the dissections of the heads of
two specimens, by Mr. R. Owen. The writer states, that this bird is
found in great abundance in the island of Jamaica, where it is known
by the name of _John Crow_; and so valuable are its services in the
removal of carrion and animal filth, that the legislature have imposed
a fine of £5 upon any one destroying it within a stated distance of the
principal towns. Its ordinary food is carrion, but when pressed hard
with hunger, it will seize upon young fowls, rats, and snakes. After
noticing the highly offensive odour emitted from the eggs of this bird
when broken, Mr. Sells relates the following instances which have come
under his own personal observation, for the purpose of proving that the
_Vultur Aura_ possesses the sense of smell in a very acute degree.
"It has been questioned whether the vulture discovers its food by
means of the organ of smell or that of sight. I apprehend that its
powers of vision are very considerable, and of most important use; but
that it is principally from highly organized olfactories that it so
speedily receives intelligence of where the savoury morsel is to be
found, will plainly appear by the following facts. In hot climates,
the burial of the dead commonly takes place in about twenty-four hours
after death, and that necessarily, so rapidly does decomposition take
place. On one occasion, I had to make a _post mortem_ examination of
a body within twenty hours after death, in a mill-house completely
concealed, and while so engaged the roof of the mill-house was thickly
studded with these birds. Another instance was that of an old patient
and much valued friend, who died at midnight; the family had to send
for necessaries for the funeral to Spanish Town, distant thirty
miles, so that the interment could not take place until noon of the
second day, or thirty-six hours after his decease, long before which
time--and a most painful sight it was--the ridge of the shingled roof
of his house, a large mansion of but one floor, had a number of these
melancholy heralds of death perched thereon, beside many more which had
settled in trees in its immediate vicinity. In these cases, the birds
must have been directed by smell alone, as sight was totally out of the
question.
"In opposition to the above opinion, it has been stated by Mr. Audubon,
that vultures and other birds of prey possess the sense of smell in
a very inferior degree to carnivorous quadrupeds, and that, so far
from guiding them to their prey from a distance, it affords them no
indication of its presence even when at hand. In confirmation of
this opinion, he relates, that he stuffed the skin of a deer full of
hay, and placed it in a field; in a few minutes a vulture lighted
near it, and directly proceeded to attack it, but finding no eatable
food, he at length quitted it. And he further relates, that a dead
dog was concealed in a narrow ravine, twenty feet below the surface
of the earth around it, and filled with briers and high canes; that
many vultures were seen sailing over the spot, but none discovered
it. I may remark upon the above experiments, that, in the first case,
the stag was doubtless _seen_ by the birds, but it does not follow
that they might not also have smelt the hide, although inodorous to
the human nose; in the second case, the birds had been undoubtedly
attracted by the _smell_, however embarrassed they might have been by
the concealment of the object which caused it. I have, in many hundred
instances, seen the vulture feeding upon small objects under rocks,
bushes, and in other situations, where it was utterly impossible that
the bird could have discovered them but through the sense of smell; and
we are to recollect, that the habit of the vulture is that of soaring
aloft in the air, and not that of foraging upon the ground."
To this account are appended the details of a minute comparison, by
professor Owen, of the olfactory nerves and the olfactory branch of the
fifth pair in the _Vultur Aura_, with those of the common turkey and
the goose. The learned anatomist concludes by saying, "the above notes
show that the vulture has a well-developed organ of smell, but whether
he finds his prey by that sense alone, or in what degree it assists,
anatomy is not so well calculated to explain as experiment."
It is far from being impossible that Mr. Waterton and Mr. Wells on one
side, and Mr. Audubon and his party on the other, may be both correct,
for in different species of vulture the power of smell may greatly
differ; we know that it does among carnivorous quadrupeds, which seek
their prey, some chiefly by sight, others by their acuteness of scent.
Among reptiles, the sense of smell appears to be at a low ratio, nor
can we suppose that it is acute in fishes. In fact, in fishes the
nasal cavities are rudimental, and do not communicate with the organs
of respiration. They are nothing more than blind sacs, placed one on
each side in front of the head, with two external openings appertaining
to each sac. The principal entrance is valvular, and on a curiously
plaited membrane in the sac itself, or on tufted or arborescent
filaments, are the ramifications of the olfactory nerves distributed.
That fishes are attracted or repelled by the odorous effluvia of
bodies, diffused either through the water itself or through the air
which the water contains, is too well ascertained to be denied. Fishes,
in fact, are attracted by certain odoriferous substances, and anglers
often use baits impregnated with some volatile oil.[20]
[20] On this subject see Izaak Walton's "Complete Angler."
We cannot for a moment doubt that insects smell; that ants and bees
are greatly directed by this sense in their search after food; that
carrion-loving beetles are thereby guided from a distance to their
repast; that the flesh-fly is led to putrescent animal substances;
and we know that the flesh-fly is sometimes deceived by the smell of
certain plants emitting a cadaverous odour, and deposits her eggs upon
them, the larvæ perishing for want of proper food. In what organ the
senses of smell in insects are placed does not appear very plain, and
the like observation applies to the _crustacea_, as crabs and lobsters,
for which baited traps are set, and into which they are allured by
their sense of smell.
No distinct organs of smell have been discovered in the mollusca,
yet it is incontestable that some of these creatures are capable of
appreciating odours. We cannot suppose that in the highly-organized
and savage cuttle-fish this sense is wanting; and we know that snails
and slugs are attracted from a distance by the odour of the favourite
plants or fruits on which they feed. The garden slugs are fond of
animal food, as we can testify, and they will pick bones with relish;
we have seen the hollow of a marrow-bone thrown into the garden filled
the next morning with slugs, which had completely cleaned it.
Whether the bivalve mollusks, as mussels, oysters, clams, etc., have
any definite sense of smell, we cannot ascertain, but we conjecture
that they are endowed with the sense of taste, for they know what to
accept and what to refuse.
We have said that man derives pleasure or disgust from the exercise of
the sense of smell, and is greatly directed thereby what to choose and
what to avoid; yet this sense harmonizes with those of sight, hearing,
and more particularly of taste, to render this world delightful to
us, if we use God's gifts aright. Has he not scattered the loveliest
flowers in garden and meadow? Has he not created fruits that gratify
alike the sight, the touch, the taste, and the smell? Has he not spread
the beauties of nature around us? Was not the garden of Eden prepared
for our first parents? Yes; but sin has entered the world, and over
flower and fruit has been the "trail of the serpent."
A few passages from the Scriptures, on which we need not comment,
will serve to show the figurative notice of, or reference to this
sense by the sacred writers, in order to influence the mind of man
through an appeal to his own sensations. "An odour of a sweet smell,
a sacrifice acceptable, well-pleasing to God," Phil. iv. 18. Works
pleasing to the Lord, deeds of charity and mercy, done by the believer
as a testimony of his lively faith, and a proof to the world that faith
engenders good works; such works, and not those of the pharisee, are
an odour acceptable to God. "Walk in love, as Christ also hath loved
us, and hath given himself for us an offering and a sacrifice to God
for a sweet-smelling savour," Eph. v. 2. Let us, who call ourselves
Christians, so walk, that our conduct before men may be after the
pattern of Him, who, in love to a fallen race, offered himself as a
sacrifice fragrant unto God the Father, that we might escape the sword
of justice. When Noah offered burnt-offerings on the altar, "the Lord
smelled a sweet savour," Gen. viii. 21; and to Him even now, O reader,
will be fragrant true penitence and faith in that Mediator, of whom the
sacrifices under the primitive dispensation were but types, and in this
sense only did they waft incense to the throne of the Almighty! The
language is altogether figurative; but how pertinent to our feelings,
and therefore how clear to our understanding, and how forcible!
5. _Touch._--Of all the senses, not one is so important to us as
that of tact or touch. It is the foundation, as it were, of all our
knowledge of the material world, and according to their elevation in
the scale of being do animals enjoy this sense in greater perfection,
and possess organs in which it is more especially concentrated. We
here distinguish, between mere feeling and touch. We consider the
wings of the bat, and the antennæ of insects, rather as feelers than
as organs of exact appreciation. The sense of feeling is diffused over
the whole surface of our body; but the sense of touch, so far as man is
concerned, resides in the hand, and especially in the pulpy tips of the
fingers.
It is true that we use the word feel when we test the qualities of
bodies with our hands, and in this sense our hands are feelers. But we
derive a knowledge from the use of our hands, which no other animal
derives from the exercise of any organ of tact it may possess. Nor
is this to be wondered at, for in all other animals tact or touch
administers only to their physical necessities. For example, the sense
of touch in the pulpy end of the beak of the snipe or woodcock must
be exquisite--multitudinous are the nerves supplying that part--for
even the soft worm or larva in the oozy ground is felt, and the
finger of man would most probably fail here; but in man the sense of
touch appeals to the mind, and communicates mental pleasure, mental
instruction, or even mental disquietude. Even as discords in music, or
grating sounds, such as the filing of a saw, or the rubbing of cork
against a wall, excite the nervous system through the mind, so does the
sense of touch disturb the mind and body when that which is touched is
discordant. A lady of the writer's acquaintance, by no means timid, and
by no means afraid of snakes, was induced to let a common snake glide
through her hand; she bore the sensation with firmness, but she nearly
fainted when the snake had crept through her grasp, and described the
working of the reptile's ribs and abdominal plates as communicating
an indescribable sensation. Yet that snake was a sort of pet, and she
used to stroke its head, and feel its lambent tongue quiver against
her hand. She was not afraid, but the sensation jarred like discordant
notes.
Were persons to write down their experiences of the pleasing and
unpleasing sensations derived through the medium of the different
senses, and were those notes collected together, we should have a mass
of most interesting and instructive information, well worthy the study
of a physiologist. After all, however, the sense of touch or tact gives
less pleasure to man than that of sight, hearing, taste, or smell; it
appreciates neither colours nor harmony, nor the flavour of luscious
viands, nor the odour of flowers and perfumes; but it communicates
greatly to his store of information. It is a "matter of fact" sense,
and though an old poet has said--
"Have you felt the wool of the beaver,
Or swan's down, ever?"
it is not one of the senses which figure on the page of poetry or
romance.
We discriminate, then, between the sense of touch and that of mere
feeling. Most probably all animals, even the lowest mollusks,
feel,--nay, even animals in which no nerves are to be discovered, as
the acalephæ, or jelly fishes; but touch is a refinement upon feeling,
which is restricted within certain zoological bounds. A learned writer
says: "The conditions on which the perfection of the sense of touch
depends are, first, an abundant provision of soft papillæ, supplied
with numerous nerves; secondly, a certain degree of fineness in the
cuticle; thirdly, a soft cushion of a cellular substance beneath the
skin; fourthly, a hard resisting basis, such as that which is provided
in the nails of the human fingers; and lastly, it is requisite that
the organ be so constructed as to be capable of being readily applied,
in a variety of directions, to the unequal surfaces of bodies, for the
closer the contact, the more accurate will be the perceptions conveyed.
In forming an estimate of the degree of perfection in which the sense
is exercised in any particular animal, we must accordingly take into
account the mobility, the capability of flexion, and the figure of the
parts employed as organs of touch."[21]
[21] Dr. Roget.
This is decidedly true as regards the higher orders of creation; but
let us look at insects--do not bees, and wasps, and flies feel? can
we watch a fly brushing its head and wings, and rubbing its little
paws against each other, without an assurance that it enjoys the sense
of touch? and what shall we say of the spider, that feels at each
thread, and "lives along its line?" Surely its sense of touch must be
sufficiently acute; yet it is limited to a certain given object, and
the spider gains only that information which bears upon its animal
necessities. But the sense of touch gives to man a number of the
properties of matter, which he retains as abstract ideas, such as
dimension, form, condition of surface, hardness, softness, elasticity,
compressibility, fluidity, quiescence, motion. In many and most
important respects it assists the eye; and, indeed, the senses of sight
and of touch appear to be correctors and supporters of each other.
As in the case of every other sense, accuracy is greatly improved by
habit, yet the qualities of matter, under the dominion of touch, are
ascertained in so correct a manner that we are scarcely ever deceived
by the knowledge thus acquired.
Dr. Fleming, in his "Philosophy of Zoology," thus writes: "The sense of
touch appears in man to be able to obtain nearly all the information,
with regard to external objects, which it is capable of receiving.
In a few instances, the lower animals surpass us in the delicacy of
the sense, as the bat, which is warned indirectly by its aid of the
presence of bodies previous to coming in contact with them. The feelers
of insects are likewise better adapted for exploring the condition
of the surface of bodies than any organ which we possess. But in all
these the sensibility of touch is limited to particular qualities, or
confined within narrow bounds. The human hand, on the contrary, by
its motions, the pliability and strength of the fingers, and their
softness, is the most extensive and perfect organ of touch possessed by
any animal."
The accuracy of the sense of touch is greatly improved by habit; and
when its resources are in constant demand, as in the instance of
persons deprived of sight, or born blind, its discriminating powers
are wonderfully increased. The same observation applies also to the
sense of hearing, which in blind persons generally is extremely acute
and accurate in its perceptions. In a Monthly Volume, published by the
Religious Tract Society, and entitled "Comparisons of Structure in
Animals: the Hand and the Arm," the reader will find a general account
of the structure and uses of the anterior limbs of man and the lower
animals, and of the substitutes for the hand, as an organ of touch and
prehension, with which many of the latter are provided.
Dr. Fleming regards the "sense of heat" as distinct from that of
touch, and, in fact, as claiming to be one of the senses. "The sense
of touch," he writes, "is exclusively occupied with examinations of
the conditions of resistance. Contact, therefore, is indispensably
requisite for enabling the organ to act upon the object, and muscular
exertion to examine its condition. Neither of these is necessary to
enable the sense of heat to act. Caloric rays emanate from a heated
body, though at a distance; and in order to ascertain their direction
and intensity no muscular effort is required. When the heated body
happens to be in contact with us, we in like manner examine its
conditions in reference to temperature without any muscular exertions,
or, rather, we try to avoid them. Thus, when I lay my hand upon the
table to examine its hardness or smoothness, I make an obvious muscular
effort with my fingers; but when I lay my hand upon the table to
examine its temperature, I endeavour to check all motion, so as to
keep my hand in the same position. These qualities of the sense of
heat sufficiently distinguish it from that of touch, with which it has
been confounded, and justify its establishment as a distinct power of
perception."
It is true that we cannot test caloric by the touch, but it does not
appear to us that an appreciation of caloric involves any other sense
than that of ordinary cutaneous feeling; the feeling of heat or cold
is a mere sensation, agreeable or painful as circumstances may be,
and it is natural that we should wish to experience that temperature
which is most congenial to us. We say that marble is cold and wood
warm, yet both may be of the same temperature; but the marble produces
a sensation of coolness, because it rapidly abstracts caloric from
the part applied to it; the skin is, in fact, a very imperfect
thermometer, yet sufficient for all ordinary purposes. It conceals
the machinery of our bodies, giving beauty of outline and appearance,
and being provided with a most minute network of nerves of sensation,
it gives us warning by the pain experienced of what things are to be
avoided. "A burned child dreads the fire" is an old saying, and a boy
who has been stung by a nettle will not rashly meddle with the plant
again.
All our senses require training and education; they are taught, even
as we are taught language. It is some time before the infant sees
distinctly, or forms any idea of size, proportion, or distance; long
before it hears accurately, and understands a word of speech; longer
still before it discriminates between musical notes; it is long
before delicious odours are relished, and long before there is much
distinction of flavour in food, for instinct directs the infant to
its mother's breast, and for many a year sweet viands are chiefly
acceptable. Habit, exercise, practice, then improve the power and
acuteness of the senses, but simple feeling is blunted by habit and
exercise.
It is, we think, Mr. Lane who tells us, that in Egypt and elsewhere,
persons who have hoarded wealth are in the habit of inflicting the
bastinado on themselves, increasing the number of strokes by degrees,
in order to inure themselves to a mode of extortion of which they
are constantly in dread. They hope to be able to weary out their
tormentors, or convince them by endurance of their poverty, and so
preserve their bags of gold and silver. Idolatrous devotees in India
accustom themselves to self-inflicted torture, and feel much less than
we might suppose; nay, even in our own country, in times of spiritual
darkness, when by mortification and penance men hoped to merit heaven,
how many have worn a shirt of horsehair till custom had made it no
hardship! The ancient Britons bore, almost unclothed, the severities
of winter; and we have read a story, but where we cannot recollect,
to the following purport:--A North American Indian was asked, how,
nearly naked as he was, he bore with such ease the summer's heat and
the winter's cold; he asked the inquirer, how his face, exposed to the
weather, endured the changes. My face, said the white man, is hardened
to it; and I, retorted the red man, am face all over.
We have said it is long before an infant is in the full use of its
bodily senses: now with regard to feeling the infant is acutely
sensitive; but who ever saw a child of a few months old examine the
qualities of objects by the touch? it cannot even manipulate; it cannot
use its hands; it has to learn the art of touch, and to improve by
practice and the exercise of the mind. For example, some persons will
pass a piece of silk or cloth between their fingers, and tell you its
quality; and so with respect to other things; this is the result of
attention and exercise.
No one is born without the organization necessary for the development
of the sense of touch, for if the arms and hands be deficient, some
other part, as the lips or tongue, will take up the function, and this
alone shows what education effects; but if a person be born deaf, or
blind, or incapable of taste and smell, (which latter appears to be
very rare, if, indeed, the case ever occur,) no other part can supply
the loss; but the loss, as far as the sight at least is concerned, is
partly compensated for by the elevation of the sense of touch; and in
this we see the immediate bearing of these two senses on each other.
The boy born blind, upon whom Cheselden so successfully operated,
believed, when first he saw, that the objects touched his eyes, as the
things which he felt touched his skin; consequently he had no idea
of distance. "He did not know the form of any object, nor could he
distinguish one object from another, however different their figure
or size might be; when objects were shown to him which he had known
formerly by the touch, he looked at them with attention, and observed
them carefully, in order to know them again; but as he had too many
objects to retain at once, he forgot the greater part of them, and when
he first learned, as he said, to see and to know objects, he forgot
a thousand for one that he recollected. It was two months before he
discovered that pictures represented solid bodies; until that time he
had considered them as planes and surfaces differently coloured, and
diversified by a variety of shades; but when he began to conceive that
these pictures represented solid bodies, in touching the canvass of a
picture with his hand he expected to find something in reality solid
upon it, and he was much astonished when, on touching those parts which
seemed round and unequal, he found them flat and smooth like the rest.
He asked which was the sense that deceived him--the sight or the touch.
There was shown to him a little portrait of his father, which was in
the case of his mother's watch; he said that he knew very well that it
was the resemblance of his father, but he asked with great astonishment
how it was possible for so large a visage to be kept in so small a
space, as that appeared to him as impossible as that a bushel could be
contained in a pint."[22]
[22] Phil. Trans., 1728.
In the Philosophical Transactions of 1826 will be found the account
of a case by Mr. Wardrop, which is very interesting; it is that of an
intelligent female of mature age, who was born blind; in her infancy,
operations were performed on both of her eyes, but they failed, one
eye being irrecoverably destroyed, and the other useless from closure
of the pupil; on this eye Mr. Wardrop successfully operated: but it
was not with joy that objects for the first time were perceived; she
was confused by the appearance of a new world, now for the first time
opened to her sense of sight; hitherto she had known it only through
the sense of touch, and touch and sight had still to be reconciled.
"On the sixth day, she said that she saw better than she had done on
any preceding day, but I cannot tell (said she) what I do see; I am
quite stupid. She seemed, indeed, bewildered from not being able to
combine the knowledge acquired by the senses of sight and touch, and
felt disappointed in not having the power of distinguishing at once
by her eye, objects which she could so readily distinguish from one
another by feeling them.
"The next day, on examining with the eye the tea-cups and saucers, and
being asked what they were--I don't know, she replied; they look very
queer to me, but I can tell in a minute when I touch them. So with an
orange which was lying before her, she could make nothing of it until
she actually touched it. When the experiment was made of giving her
a silver pencil-case and a large key to examine with her hands, she
discriminated and knew each distinctly; but when they were placed on
the table side by side, though she distinguished each with her eye, yet
she could not tell which was the pencil-case and which the key.
"In six weeks after the operation, she returned home. At this period,
she had learned a great deal; she had acquired a pretty accurate notion
of colours, but with regard to forms and distance she was still very
ignorant. She had also great difficulty in directing her eye to an
object, so that when she attempted to look at anything she turned her
head in various directions, until her eye caught the object of which
it was in search. She still entertained, however, the same hope, which
she expressed soon after the operation, that when she got home, her
knowledge of external things would be more accurate and intelligible,
and that when she came to look at those objects which had been so long
familiar to her touch, the confusion which the multiplicity of external
objects now caused would in a great measure subside."
Thus, then, it is from an association between the senses that
correctness and precision in any one sense are acquired; and especially
do the eye and hand support each other, and supply each other's
deficiencies till both have learned their perfect lesson. I can stretch
my hand out to any object before me with certainty, so truly does the
eye tell me whether it is within my reach or not, but the eye first
learned that faculty from the hand, after long discipline and many
trials. Afterwards the eye speaks a silent language to the hand, and
is understood. Under what merciful circumstances are they placed that
possess all their faculties and senses! but, alas! how many are there
that never dream of thanking a merciful God for his unbounded kindness!
nay, there are some atheistical materialists who believe, or rather
pretend to believe, that man's exquisite organization, and that of
animals and plants, is self-developed--how, they do not condescend to
explain; for, granting them their premises, namely, that matter is
eternal--and what then? it must be inert, and neither the laws of
vitality nor chemistry, involving electricity and galvanism, could
be taken on by inert particles--all would be chaotic, did not God
govern, arrange, and order all. It is he who has created man, and,
fallen as man is, he still is an object of God's care; for he sent
his well-beloved Son into the world for our redemption, and the time
is coming in which all nations shall know the Lord, and adore him in
sincerity and truth.
Like all the organs of our senses, the hands are the instrument of
wickedness to sinful man; his sense of touch is the inlet of evil. How
refined that sense in the adroit pickpocket, but to what an ill purpose
is it devoted! How dexterous are the hands of the shoplifter, but to
what a wretched course have they been trained! The hand grasps the pen;
every stroke is guided by its delicate sense of touch; it obeys the
mind; and, oh! what dictations from the depraved mind have polluted
society! God has been reviled, Jesus Christ denied, the Holy Spirit
mocked, and in letters written by hands which the almighty Maker and
Preserver had endowed so supereminently. Their hands are mouldering;
dust has returned to dust; but where are the immortal spirits which
directed those hands to scatter poison abroad? It is not for us to
inquire or judge. Let us, ourselves, be watchful, and let our hands be
clean in the sight of God; let us be diligent in business, serving the
Lord; let us fight the good fight of faith, and lay hold on eternal
life!
Though we have described the hand as the great and main organ of touch,
let it be understood that it is not the first called into operation.
The hand requires rigid discipline; for a long period it is useless
as an organ of tact; yet, when educated, how perfect, how precise!
But it is made what it is by education. Our ideas coincide exactly
with those of sir Charles Bell, who thus writes: "The lips and the
tongue are first exercised; the next motion is to put the hand to the
mouth in order to suck it; and no sooner are the fingers capable of
grasping, than whatever they hold is carried to the mouth; so that
the sensibility to touch in the lips and tongue, and their motions,
are the first inlets to knowledge, and the use of the hand is a later
acquirement."
Another passage from the same gifted writer is as follows: "The first
office of the hand, then, is to exercise the sensibility of the mouth;
and the infant as certainly questions the reality of things by that
test, as the dog does by its acute sense of smelling. In the infant,
the sense of the lips and tongue is resigned only in favour of the
sense of vision, when that sense has improved, and offers a greater
gratification, and a better means of judging of the qualities of
bodies. The hand very slowly acquires the sense of touch; and many
ineffectual efforts are seen in the arms and fingers of the child,
before the direction of objects or their distance is ascertained.
Gradually the length of the arm, and the extent of its motions, become
the measure of distance, of form, of relation, and perhaps of time."
Throughout life, the sensibility, as it regards tact, of the tongue
and lips continues paramount; we can feel the slenderest hair with our
tongue, which our hands would not appreciate: but, on the contrary,
size, form, distance, order, and the general qualities of matter,
can only be gained through the hand, after a persevering discipline.
A blind man may examine a statue with his hands, and pronounce upon
its excellence; and this fact suggests to us an idea of sir Charles
Bell, who says: "The knowledge of external bodies, as distinguished
from ourselves, cannot be acquired until the organs of touch in the
hand have become familiar with our own limbs. We cannot be supposed
capable of exploring anything by the motion of the hand, or of judging
of the form or tangible qualities of an object pressed against the
skin, before we have a knowledge of our own body as distinguished from
things external to us." From these remarks we naturally slide into a
dissertation on a sense, allied to that of touch, but yet different--we
mean muscular sense.
6. _Muscular sense._--God in his infinite wisdom has constructed all
living things, and no doubt there is much yet for the philosopher to
discover in the organization of animal bodies; there is, moreover,
something that he never will understand, namely, life intrinsically
considered, and the manner in which the immortal spirit and the
dying body communicate with and influence each other. But though
these points must ever remain a mystery, still there are those the
obscurity of which science has to a certain degree dispelled, and it
was reserved for a late scientific anatomist to prove to the world,
that the nerves of sensation and the nerves of motion are essentially
distinct, although interblended together they pervade every muscle.
Hence, as this philosopher observes, (we mean sir Charles Bell,) we
are sensible of the action of our muscles, because these muscles have
two classes of nerves; and he found that in exciting one of these the
muscle contracted, while on exciting the other no action took place.
The nerve which had no power to make the muscle contract was the nerve
of sensation.
Continuing his experiments, he proved that there is a nervous circle
connecting the muscles with the brain, that one nerve is not capable
of transmitting what is called the nervous spirits in two different
directions at one instant of time, but that for the regulation of
muscular action there is a nerve of sensibility, to convey a sensation
of the condition of the muscles to the sensorium, as well as a nerve
of motion for conveying the mandate of the will to the muscles. He
also demonstrated, that in their distribution through the body, the
nerves which possess these two distinct powers of conveying sensation,
and of exciting the muscles to contraction, are wrapped up, or, as
it were, woven together in the same sheath, and that they present to
the eye the single appearance of one nerve. It was only by examining
the nerves at their roots, that is, where they arise from different
tracts of the brain and spinal marrow, and before they coalesce, that
this philosophic anatomist succeeded in demonstrating their distinct
functions. In the face, the nerve of motion passes by a circuitous
route, apart from the nerve of sensation, to be distributed to the
muscles; and, therefore, the distinct characters of these two nerves
were, as sir C. Bell asserts, more easily proved by experiment than in
any other part of the body.
The nerves of sensation then feel, or rather recognise, those actions
of the muscles which are excited through the medium of the nerves of
contraction, and these nerves of contraction, as far as the voluntary
muscles are concerned, obey the commands of an immaterial being--mind,
spirit, soul; in the lower animals, so far as we know, this principle
is transient, for they have no ideas of life, or of death, or of
futurity; but in man, the soul is immortal, and for the future bliss of
this immortal essence revelation affords a certain guide.
Now the sense of touch and the muscular sense have, by most writers,
been confounded together; hence, we are told that weight is determined
by touch, but this is erroneous; it is determined by the muscular
agency and sense, under the dictation of the will. The abbé Nollet says
of touch, that "it not only puts it in our power to judge of what makes
an impression upon us, but also of what resists our impulsions." Here
the sense of touch and the muscular sense are confounded together. The
agency of touch has nothing to do with weight or resistance; and herein
we differ from Dr. Fleming, and agree with sir Charles Bell, by whom,
indeed, this muscular sense was first demonstrated. To feel, or touch,
is not to resist or struggle. Laocoon, striving with the serpents,
resists--his muscular sense is called into action, as is that of the
wrestler when engaged in a trial of skill or strength; but what has
muscular feeling to do with that tact, which distinguishes between
the texture of tissues, or the smoothness or roughness of bodies? For
ourselves, we refer the sensations of hardness and softness rather to
a muscular sense than a simple sense of touch; but, as we have said,
the sense of touch and the muscular sense, or sense of resistance,
inter-amalgamate with each other, nevertheless, there is a definite
muscular sense of which every one is conscious, and it is by the
education of this sense that the infant learns to walk, the man to
ascend the lofty ladder, or traverse the ledge of the precipice. It is
not connected with feeling alone, but also with sight; and, indeed, the
senses of sight, feeling and support, or resistance, are in as close
relationship, as are those of smell and taste. This is exemplified in
the fencer, whose muscular sense obeys his eye, and in the artist, who
strikes out the bold outline of a figure on the canvass.
This muscular sense is sometimes called the sense of motion; and
rightly, because it is a feeling of muscular action; not a feeling
of extraneous bodies, but a feeling of what passes within ourselves,
as far as such feeling is permitted (many internal operations go on
without our consciousness)--a feeling of what we do, according to our
will, and the permission of God Almighty. Does the uninstructed man,
who looks upon and admires a lovely landscape, think about the inverted
picture on his retina? No. Does the athlete who lifts a great weight
think of the biceps, or the deltoid, or the pectoral muscles? No. But
does he not feel, while he strives, while he struggles, while he runs,
an internal consciousness of action totally distinct from touch?
This perception is termed by sir Charles Bell the "muscular sense." He
thus illustrates his idea: "When a blind man, or a man with his eyes
shut, stands upright, neither leaning upon nor touching aught, by what
means is it that he maintains the erect position? The symmetry of his
body is not the cause. The statue of the finest proportions must be
soldered to its pedestal, or the wind will cast it down. How is it,
then, that a man sustains the perpendicular posture, or inclines in a
due degree towards the winds that blow upon him? It is obvious, that he
has a sense by which he knows the inclination of his body, and that he
has a ready aptitude to adjust it, and to correct any deviation from
the perpendicular. What sense, then, is this? for he touches nothing,
and sees nothing; there is no organ of sense hitherto observed which
can serve him, or in any degree aid him. Is it not that sense, which
is exhibited so early in the infant in the fear of falling? Is it not
the full development of that property which was early shown in the
struggle of the infant, while it lay in the nurse's arms? It can only
be by the adjustment of muscles that the limbs are stiffened, the body
firmly balanced and kept erect. There is no other source of knowledge
but a sense of the degree of exertion in his muscular frame, by which
a man can know the position of his body and limbs, while he has no
point of vision to direct his efforts, or the contact of any external
body. In truth, we stand by so fine an exercise of this power, and the
muscles are, from habit, directed with so much precision and with an
effort so slight, that we do not know how we stand. But if we attempt
to walk on a narrow ledge, or stand in a situation where we are in
danger of falling, or rest on one foot, we become then subject to
apprehension; the actions of the muscles are, as it were, magnified,
and demonstrative of the degree in which they are excited.
"We are sensible of the position of our limbs; we know that the arms
hang by the sides, or that they are raised and held out, although we
touch nothing and see nothing. It must be a property internal to the
frame by which we thus know the position of the members of our body;
and what can it be but a consciousness of the degree of action,
and of the adjustment of the muscles? At one time, I entertained a
doubt whether this proceeded from a knowledge of the condition of the
muscles, or from a consciousness of the degree of effort which was
directed to them in volition. It was with a view to elucidate this that
I made the observations which terminated in the discovery that every
muscle had two nerves; one for sensation, and one to convey the mandate
of the will, and direct its action. I had reasoned in this manner: we
awake with a knowledge of the position of our limbs; this cannot be
from a recollection of the action which placed them where they are; it
must, therefore, be a consciousness of their present condition. When a
person in these circumstances moves, he has a determined object, and
he must be conscious of a previous condition before he can desire a
change, or direct a movement."
In walking, riding, swimming, and other bodily exercises; in writing,
playing on the piano, or any other instrument of music, the muscular
sense is called into activity, and co-operates with the senses of
sight, touch, etc. Muscular exertion is in itself pleasurable, when
not pushed too far; and, indeed, the healthy condition, both of the
body and mind, results from muscular exertion, and the alternations
of activity and repose. The appointment of man, after the fall, to a
life of labour, was a judgment tempered by mercy. Man is not destined
to lead a life of sloth or supineness, but, urged on by his natural
wants, he cultivates the ground, he tames the wild beast of the forest
or mountain, he builds houses, he constructs ships, he clothes himself
with fabrics, he surrounds himself with the comforts, the decencies,
the luxuries of life, and in every work which his hands find to do his
muscular sense is in requisition; it is this sense which appreciates
resistance, which enables us to balance our bodies, to move with
gracefulness, to run, to walk, to leap, to throw the shuttle with
precision, or wield the hammer with skill. It is improved by education;
the child learns first to walk, and then to run and leap, and in due
time to know its own strength, and also the best mode of employing
that strength, without reflecting upon the laws of mechanics, or any
philosophic theories. It is evident, then, that we have "a perception
of the condition of the muscles previous to the exercise of the will,"
and that with respect to the hand, "it is not more the freedom of its
action which constitutes its perfection, than the knowledge which we
have of these motions, and our consequent ability to direct it with the
utmost precision."
That the lower animals are endowed with this muscular sense cannot be
doubted. It enables the tiger to spring with accuracy upon his prey,
the cat upon the mouse, the greyhound in pursuit of the hare when to
make the fatal snap, and the horse to leap the fence, which his eye
tells him is within his power; it teaches the loris to creep upon
its victim, as slowly but as surely as the hand on the clock-face
traverses the dial-plate, and attains the given number; it is
immediately connected with instinct, and man, when he steps aside to
avoid a threatened stroke, or raises his arm to parry a blow, puts the
muscular sense into exercise.
The muscular sense is, to use a homely expression, an every-day working
sense; touch and sight are its prime supporters, and to these in turn
it lends its aid. Nevertheless, to a certain degree it is independent
of them; the infant seeks the breast as it were by an instinctive
impulse, or applies the coral to its mouth; and in the dark as well
as in the light, we transmit our food directly and precisely to the
organs of mastication and deglutition, without thinking upon the manner
in which the varied actions are performed, or even transiently noting
them. We _will_ to perform an act within our power of achievement, and
by the complicated action of muscles, nerves, vessels, and bones, we
accomplish our object, at the same time, perchance, we know not the
origin and insertion of a single muscle, the direction of a single
nerve, the course of a single artery.
The muscular sense is, in fact, in perpetual exercise; it is intimately
connected with self-consciousness, for we feel that we corporeally
exist, that other bodies exist around us, that they resist us, that
they lead us to calculate our own powers, nor will all the arguments of
the school of Berkeley convince us that we exist only in idea. When Dr.
Johnson stamped upon the ground to disprove Berkeley's idea, he was
right.
So much for the senses with which we are endowed, and the information
which the mind receives through their respective channels. They teach
us all that we know concerning the qualities of matter, and they
subserve many of our enjoyments--they are essential to our comfort,
our activity, our usefulness; but we gain through their medium no
abstract truths, no determinate principles. These are elaborated in
the mind itself by its own self-analysis; but, then, they do not teach
us our own position as it respects time and eternity. The wisest
of the heathens of Greece or Rome lived in doubt, entangled in the
mazes of a vain system of philosophy; and though they might believe
in a god, or in gods, deducing their arguments as to the existence
of an all-powerful Being from the works of nature, and from that
internal conviction which seems common to the human race--they knew
nothing of His attributes, of his laws, of his requirements, of man's
fallen nature, of the intrinsic sinfulness of the heart, of the means
of grace, of a hope of glory. They could write noble poems, deep
philosophic treatises, histories of empires, narratives of events,
details of characters, descriptions of works of art; they could carve
statues of matchless perfection, and build temples of surpassing
splendour. They displayed an intellectual pre-eminence, which still
sheds a lustre over the civilized world. Who by searching can find out
God? Unless God graciously reveals himself to us, a true knowledge of
him in our fallen state is impossible; the capabilities of our minds
are, after all, but limited; and though, through reflection on the
evidences of our senses, we may come to the conclusion that there is
an omnipotent Power, we remain in ignorance as to what that Power is,
and as to our relationship thereunto. Hence, then, the necessity of
information beyond what the mind can gain through the senses, or by its
own reflex operations; we are conscious of our position as respects
the lower animals, and we have natural longings after and hopes of
immortality; the soul whispers to itself, _Non omnis moriar_, I shall
not all die; but here, were it not for revelation--a revelation from
God, we should be left in darkness.
God gave a revelation of his will to Adam; our first parents
transgressed, but then in mercy a promise was given, that the seed
of the woman should bruise the serpent's head. God gave a further
revelation of his will to Moses, with promises and commands, and
elected from among the nations a peculiar people, of whom from the line
of Jesse after the flesh should arise the Messiah; in Him are all the
promises and prophecies centred, and through him the great revelation
of God's purposes of mercy to a fallen world was ordained to be
published. The Messiah came; He of whom Isaiah prophesied; the despised
and rejected of men--God manifest in the flesh. The prophet's words
were verified, "He was wounded for our transgressions, he was bruised
for our iniquities: the chastisement of our peace was upon him; and
with his stripes we are healed."[23]
[23] Isa. liii. 5.
This is the Christian revelation, which, while it shows us our lost and
sinful nature, our utter unworthiness, and the insufficiency of good
works for salvation--whilst it humbles our pride, and self-sufficiency,
and teaches that our place before God is in the dust, yet it speaks
of joy and peace, for it points out what is all-important, the mode
of redemption, the forgiveness of our sins, our adoption as heirs of
the kingdom of heaven. "In this was manifested the love of God toward
us, because that God sent his only begotten Son into the world, that
we might live through him."[24] God reveals himself in his works as
a God of wisdom and power; but here he discovers himself as a God of
truth, justice, and mercy. He reveals himself as the triune Jehovah,
the Father, the Son, and the Spirit, one God for evermore; and he gives
us a revelation of the plan of salvation. And what is this plan? it
is one by which justice and mercy are reconciled. "Without shedding
of blood is no remission" of sins. The Son of God, according to the
Divine promise, took upon himself our human nature, dwelt upon earth,
sinless, and offered himself up as a sacrifice for sin on Calvary. He
"who, being in the form of God, thought it not robbery to be equal with
God: but made himself of no reputation, and took upon him the form
of a servant, and was made in the likeness of men: and being found in
fashion as a man, he humbled himself, and became obedient unto death,
even the death of the cross. Wherefore God also hath highly exalted
him, and given him a name which is above every name: that at the name
of Jesus every knee should bow, of things in heaven, and things in
earth, and things under the earth; and that every tongue should confess
that Jesus Christ is Lord, to the glory of God the Father."[25]
[24] 1 John iv. 9.
[25] Philippians ii. 6-11.
Of the sacrifice of Christ, the crowning sacrifice, those of the Mosaic
ritual were types or emblems. By his sacrifice the claims of the law
were satisfied. What is required of us? Belief in the atonement. "Jesus
said unto Martha, I am the resurrection and the life: he that believeth
in me, though he were dead, yet shall he live: and whosoever liveth and
believeth in me shall never die."[26] A true, living, justifying faith
is the gift of the Holy Spirit, who sanctifies and renews the heart of
the genuine believer. "The carnal mind is enmity against God: for it
is not subject to the law of God, neither indeed can be;" but when the
mind is enlightened by grace Divine, the awfulness of sin is perceived
and deeply felt, true repentance is awakened, love and gratitude to God
for every mercy are excited, and the soul is warmed with adoration.
Then does the converted man become prayerful and watchful; then is he
zealous in God's cause, and anxious for the conversion of those that
live in the darkness of ignorance, and travel along the broad road that
leadeth to destruction. Then will he be patient and trustful under
trials and affliction, and justify God's dealings with man.
[26] John xi. 25, 26.
Such are the truths revealed by God himself, which through nothing
but direct revelation could have enlightened, cheered, animated, and
guided the human affections and will. Man, as an immortal being, has
not been left to himself. True it is, that there are many nations still
in darkness, and some in the most degraded ignorance. To ask why this
is so, is to ask the reasons which determine God in his purposes; we
see as in a glass darkly, and the deep things of God are hidden from
our eyes; but we are assured that the time will come when all nations
shall know the Lord, and Christ shall reign in fulness of glory. Let
us be thankful if our trust is in Christ, if he is in us the hope of
glory, for "eye hath not seen, nor ear heard, neither have entered into
the heart of man, the things which God hath prepared for them that love
him."
We have sufficiently shown the necessity of a revelation to man
relative to things essential to his eternal interest, but of which
he could gain no knowledge by his own mental exertions. We know by
internal conviction that we are immortal beings; but unguided by
revelation, we shall look forward to the future with anxiety, with a
sort of vague apprehension, but revelation dispels anxiety, and fills
us with all "joy and peace in believing."
Dr. Abercrombie, in his work on the Intellectual Powers, says: "There
is thus, in the consciousness of every man, a deep impression of
continued existence. The casuist may reason against it till he bewilder
himself in his own sophistries; but a voice within gives the lie to his
vain speculations, and pleads with authority for a life which is to
come. The sincere and humble inquirer cherishes the impression while he
seeks for further light on a subject so momentous; and he thus receives
with absolute conviction the truth which beams upon him from the
revelation of God, that the mysterious part of his being, which thinks,
and wills, and reasons, shall, indeed, survive the wreck of its mortal
tenement, and is destined for immortality."
How mysterious is the union between mind and matter! how little we
know of ourselves! how shallow is our deepest philosophy! We know that
the mind is that part of our being which thinks and wills, reasons and
remembers, but we know nothing of it except from these functions. "By
means of the corporeal senses it holds intercourse with the things
of the external world, and receives impressions from them, but of
this connexion also we know nothing but the facts; when we attempt to
speculate upon its nature and cause, we wander at once from the path
of philosophical inquiry into conjectures, which are as far beyond
the proper sphere as they are beyond the reach of human faculties.
The object of true science on such a subject, therefore, is simply
to investigate the facts or relations of phenomena, respecting the
operations of mind itself, and the intercourse which it carries on with
the external world."
In a philosophic point of view, all our knowledge of the world around
us is referable to the operations of the mind on the impressions
conveyed to it through the senses, that is, perception. Nevertheless,
in point of fact, the knowledge which is acquired by an individual
through perception and mental agency, as reflection, memory, etc.,
is but a small part of what he possesses; it is to the perception
and mental labour of others that he owes the great mass of knowledge
he is gifted with. Generation after generation has contributed to
accumulate a store of facts, a treasury of thoughts and reflections,
to which succeeding generations have added, leaving them as a legacy
to generations yet to come, who will contribute in their turn to
the stock, and bequeath the treasure to their successors. Thus are
we enriched by the labour of others, and not altogether by our own
experience.
Herein is a wide hiatus between man and the most sagacious of brutes.
The brute gains all from personal experience; no generation can build
upon the foundation left by a preceding generation--but man can; and
it is no objection to allege, that some races remain in a savage
state for ages; they possess the power, the capability, the mental
constitution, which the brute does not. Besides, they do improve under
favourable circumstances. What were the Anglo-Saxon marauders, our
own ancestors? Savages. Is England now a savage country? What were
the Celtic British in Cæsar's time? Savages. Were they savages when
the Romans had held possession of the island for three hundred years?
No; they had adopted the arts, the manners, the civilization of their
conquerors. How this very fact of the capability of man to give and
receive knowledge demonstrates his superiority in creation! It is true
that the human intellect is limited, and that there are mysteries into
which he cannot penetrate; nor is it needful for his welfare, his
improvement, his happiness, his hopes of a joyful immortality, that he
should be able to do so. Let him rely on the oracles of God. Mysteries,
indeed, surround him. How fluently does he talk about matter, yet he
knows nothing about it, excepting what he gains through his senses; and
this knowledge is limited to certain qualities, which may be termed
primary and secondary. The primary qualities of material bodies are
in themselves essentials, namely, solidity and extension. We cannot
conceive of matter, without an involvement of these two properties. The
secondary qualities of matter are colour, texture, temperature, smell,
taste, etc., properties which differ in different bodies, and which are
fluctuating, changeable, uncertain. Of these, and other properties of
matter, as motion, sound, lightness, or heaviness, etc., our senses are
the external tests, though mind is, in reality, the discriminator.
"Our first knowledge of the existence and properties of the material
world is evidently of a complex nature. It seems to arise from the
combined action of several senses, conveying to us the general notion
of certain essences, which are solid and extended, or possessed of
those properties which characterize material things. Without this
general knowledge previously acquired, our various senses, acting
individually, could convey to us no definite notion of the properties
of external things. A smell, that is a mere odour, for example, might
be perceived by us, but would convey nothing more than the sensation
simply. It could not communicate the impression of this being a
property of an external body, until we had previously acquired a
knowledge of the existence of that body, and had come by observation to
associate the sensation with the body from which it proceeds. The same
holds true of the other senses, and we are thus led at the very first
step of our inquiries to a complicated process of mind, without which
our mere sensations could convey to us no definite knowledge."[27]
[27] Abercrombie.
Here, then, we conclude. Let us give thanks and praise to that God
who has made us what we are--instruments of countless strings, all
in harmony, the music of which reaches the soul, and in the secret
recesses of the mind is there analyzed, reflected upon, compared, and
stored up as knowledge. We feel, we see, we hear, we smell, we taste,
we resist; we are assured of our own individuality; we are conscious of
our own existence, and we know that all around is external to our own
individuality. That sense of individuality is in the mind, and we have
within us the assurance of immortality. Let us look to Him, who is the
Saviour from an immortality of despair, that at the day of judgment
we may be found clothed in his robe of righteousness, the garment of
salvation.