ANATOMY, 
clous faculty in a very eminent degree. The powers and 
virtues of medicinal plants are hardly to be better known 
than by the teflimony of tailing and fmelling. Hence it is, 
that in all animals thole organs are placed together; and 
lienee the fmelling is flronger, and the organs larger, in thole 
animals which feek their prey at a conliderable diliancc, or 
are to rejedt malignant plants from among thoi'e lit for food. 
The fenfe of fmelling is performed by means of a loft 
pulpy membrane, full of pores and fmall velfels, v. Inch 
lines the whole internal cavity of the nollrils; it is thick¬ 
er upon the feptum and principal convolutions, but thin¬ 
ner in the finufes. The nerves of the nofe, being almoft 
naked, require a defence from the air, which is continu¬ 
ally drawn through the nollrils, and blown out again by 
refpiration. Nature has therefore fupplied this part, which 
is the organ of fmelling, w ith a thick infipid mucus, very 
fluid in its firft feparation, but, by the air, condenling in¬ 
to a thick, dry, and more confident, crud. By this mucus 
the nerves are defended from drying and from pain. It 
is poured out from many fmall arteries, and depodted 
partly into numerous cylindrical dudts, and partly into 
round vifible eryptx or cells, fcattered all over the nodrils. 
It flows out all over the furface of the olfadtory mem¬ 
brane, which is anointed with it on all (ides. This mucus 
is accumulated in the night-time; but, in the day, it ei¬ 
ther flows fpontaneoufly, or may be more powerfully ex¬ 
pelled by blowing the nofe. By becoming dry and harfli, 
it irritates the very fenflble nerves of the membrane, 
tvhence a fneezing is excited for its removal. The tears 
defcend, by a channel proper to themfelves, into the ca¬ 
vity of the nofe, by w hich they moidenand dilute the mucus. 
The air, filled with the fubtle and invilible effluvia of 
bodies, confiding of their volatile, oily, and faline, parti¬ 
cles, is, by the powers of refpiration, urged through the 
nofe, and applied to the almod naked, and condantly foft, 
olfactory nerves, in which a kind of feeling is excited, 
which we call fmelling ; and by this fenfe we didinguidt 
.feveral kinds of oils and falls, by different feents or odours, 
which are difficultly reducible to daffies, and difficultly 
recalled to memory. This feent ferVes to admonifh us of 
pernicious putrefaction ; of violent acrimony; or of a mild 
and foapy quality in bodies. As fait, joined with an oil, 
is the objedt of tade; and a volatile oil, added to falts, 
ferves to excite fmells, we may perceive the affinity of 
thefe two fenfes, which affinity feemed to be the more ne- 
celfary on account of thefe fenfes mutually and jointly af- 
fiding each other in performing their offices. Volatile par¬ 
ticles are chiefly didinguidied by fmell, and fixed ones by 
tade ; perhaps becaufe the thick mucous cuticle, fpreadover 
the tongue, intercepts the aftion of the more fubtle faline ef¬ 
fluvia from aCting upon the tade, which yet eafily adcCt the 
fofter and lefs covered nerves of the internal nofe. 
The power of odours is drong and quick, becaufe mi¬ 
nute particles of matter are immediately applied to naked 
nerves fituated very near the brain. Hence the force of 
poifonous vapours, and hence alfo the quality certain odours 
poflefs, of recovering people from faintings, or after drown- 
ing. Hence alfo that violent fneezing wdiich often arifes 
from acrid particles, and a diarrhoea from the fmell of 
fome medicines; hence the power of particular antipa¬ 
thies. Hence alfo the pernicious effeCts of exceffive fneez¬ 
ing, more efpecially in producing blindnefs, which may, 
in fome meafure, alfo be more eafily brought on by the 
confent of the nerves that are exceedingly numerous in 
the neighbouring organs. Among the various parts of the 
nofe, the feptum, and more efpecially the os turbinatum, 
have a confiderable lhare in the organ of fmelling, fince 
thefe parts are multiplied in quick-fcented animals. In 
dogs, and other quadrupeds, they are prodigioully length¬ 
ened, and beautifully formed into fpiral laminae ; in filhes 
they are elegantly formed, like the teetli of a comb. 
OF. THE EAR. 
Anatomifts commonly divide or diflinguilh the ear into 
external and internal. The greateft part of the external 
Vol, I. No. 38. 
601 
ear confifis of a large cartilage, very artificially framed, 
which is the balls of all the other parts of which this por¬ 
tion of the ear is compofed. The internal ear confifis 
chiefly of feveral bony pieces, partly formed.in the fub- 
ftance of the os temporis, and efpecially in that portion 
of it called apoplyjis petrofa; and partly feparuted from, 
but contained in, a particular cavity of that bene. Two 
portions'are difimguilhed in the external ear; one large 
and folid, called pinna, which is the fuperior, and by much 
the greater; part; the other fmall and foft, called the lobe , 
which makes the lower part. The fore-fide of the ear is 
divided into eminences and cavities. The eminences are 
four in number, called helix, antihelix, tragus, and antitras 
gus. The helix is the large folded border or circumfe¬ 
rence of the great portion of the ear. The antihelix is 
lire large oblong eminence, furronnded by the helix. The 
tragus is the fmall anterior protuberance below the ante¬ 
rior extremity of tire helix. The antitragus is the pofte- 
rior tubercle, below the inferior extremity of the antihe¬ 
lix. The cavities on the for'e-fide are four in number: 
the hollow of tire helix ; the depreffion at the fuperior ex¬ 
tremity of the antihelix, called fojf'a navicular is ; the con¬ 
cha, or great double cavity ; and the meatus, fituated at 
the lower part of the bottom of the concha. The lobe of 
the ear, or that foft portion which lies under the tragus, 
antitragus, and meatus auditorius, is made up of nothing 
but Ikin and cellular fubflance. The meatus auditorius 
is partly bony and partly cartilaginous. The (kin which 
covers the cartilage contains a great number of fmall 
glands, which continually difeharge an oily whitilh hu¬ 
mour, colledted chiefly near the adhelions of the ear to 
the head, and under the fold of the helix ; and thele glands 
are of the febaceous kind. The fkin, which lines the me¬ 
atus auditorius, contains another kind of glands, of a yel- 
lowilh colour. Thele glands are difpofed in Inch a man¬ 
ner as to leave reticular fpaces between them, and they 
penetrate a little way into the fubflance of the (kin. They 
are are called glandulae ccruminofce, becaufe they difeharge 
that matter which is named cerumen , or the wax of the ear. 
The bony part of the organ of hearing may be divided 
into four general parts: 1. The meatus auditorius e-xter- 
nus; 2. The tympanum ; 3. The labyrinth; 4. Themea- 
tus auditorius interims. It may likewife be divided imp 
immoveable or containing parts, which take in all the four 
already mentioned ; and moveable or contained parts, 
which are four little bones lodged in the tympanum, call¬ 
ed incus, malleus, Jlapes, and os orbiculare or lenticulare. The 
external auditory palfage begins by the external auditory 
hole, the edge of which is rough and prominent; but, 
backward toward the maftoid procefs, it appears very 
much Hoped. 
The tympanum, or drum of the ear, is a cavity fome- 
what fpherical, or rather hemifpherical, the bottom of it 
being turned inward. The tympanum contains feveral 
little bones, called the bones of the car. They are gene¬ 
rally four in number, denominated from fomething to 
which they are thought to bear a refemblance, viz. incus, 
malleus, flapes, and os orbiculare or lenticulare. The in¬ 
cus, or anvil, refembles, in fome meafure, one of the an¬ 
terior dentes molares, with its roots at a great diflance 
from each other. It may be divided into a body, and two 
branches or legs ; one of the legs is long, the other flioi t. 
The malleus, or hammer, is a long bone, with a large 
head, a fmall neck, a handle, and two procelfes; one in 
the neck, the other in the handle. The (tapes is a fmall 
hone, very well denominated from the refemblance it bears 
to a flirrup. It is divided into the head, legs, and balls. 
The head is placed'upon a fliort flatted neck. The two 
legs form an arch like that of a flirrup ; in the concave fide 
of which is a groove that runs through their whole length. 
The hafis refembles that of a flirrup, both in its oval 
fliape and union with the legs, but it is not perforated. 
The os orbiculare, or lenticular bone, is the fmallefl bone 
in the body. It lies between the head of the flapes and 
extremity of the long leg of the incus, being articulated 
7 O with 
