time. This membrane is the ufual feat of impoftumations and boyls, in both which nature, uninterrupted, always corrodes a hole in the skin, from whence we may learn that the best way of opening any impoftumation is by a hole, and that too as near the time of its breaking naturally as may be, that nature may make the utmost advantage of the discharge. There is fome→ times a large kind of boyle or carbuncle in this membrane, which first makes a large flough and a number of small holes through the skin which in time mortifies and cafts off, but the longer the flough is fuffered to remain the more it discharges, and the more advantage to the patient; at the latter end of which cafe the matter has a bloody tincture, and a bilious fmell, exactly like what comes from ulcers in the liver; and both thefe cafes are attended with fweet urine as in a diabetes.

MAMMA, the BREASTS, feem to be of the same structure in both fexes, but largest in women. Each breaft is a conglomerate gland to separate milk, with its excretory ducts; which are capable of very great diftention, tending toward the nipple, which as they approach, they unite, and make but a few ducts at their exit. There are to be met with in authors instances attested of mens giving fuck, when they have been excited by a vehement defire of doing it and it is a common obfervation, that milk will flow out of the breafts of new born children, both male and female,

THE breafts and uterus in women, the tongue, mouth, and penis in men, and the eyes in children, are the parts moft fubject to cancers; yet there is no part where this disease has not fometimes fixed. It is a matter of difpute among fome furgeons, whether cancerous tumors should ever be extirpated or not, though it is certain none of these ever were cured without, and being extirpated, there have been many. The objection against extirpation is this, that the operation often provokes the part which otherwife might lye quiet: but I do not think this is true; in defperate cafes, where we cannot extirpate, we find the best remedy is plentiful bleeding (which alfo is natures last refort) gentle conftant evacuations by stool, and a vegetable dict; and though phyfic never cures while the tumor remains, yet after extirpation it is highly ufeful, and even the worst conftitutions have fometimes been brought to their primitive state. An eminent furgeon in the city having a patient with a cancerated breast, extremely large, and fo much ulcerated that the ftench of it was infupportable; fhe infifted upon the extirpation against all advice, with no other hopes but to be delivered from the offenfive fmell. Some time after the operation the wound looking extremely fordid, he fprinkled it all over with red mercury precipitate, which put the patient into a high falivation, upon which the breaft grew clean and healed, the patient recovered, and, contrary to all expectation, lived many

years

years in good health. From this accident I learnt the usefulness of falivating after extirpating cancerous tumors, though nothing is more hurtful before. In the extirpation of a breast and all other tumors, as much skin as is poffible should be faved, for the lofs of a great deal of fkin is fufficient to make an incurable ulcer in the most healthful body, and much more so in a bad constitution.

CHAPTER II.

Of the membranes in general.

VERY diftinct part of the body is covered,

EVE

and every cavity is lined with a fingle membrane, whose thickness and strength is as the bulk of the part it belongs to, and as the friction to which it is naturally expofed.

THOSE membranes that contain distinct parts, keep the parts they contain together, and render their furfaces smooth, and lefs fubject to be lacerated by the actions of the body; and those which line cavities ferve to render the cavities smooth and fit for the parts they contain to move against.

THE membranes of all the cavities that contain folid

parts, are studded with glands, or are provided with veffels, which feparate a mucus to make the parts contained move glibly against one another, and not grow together; and thofe cavities which are exposed to the air, as the nofe, ears, mouth,

and

and trachea arteria, have their membranes befet with glands which feparate matter to defend them from the outer air. Those membranes that have proper names, and deferve a particular defcription, will be treated of in their proper places.

CHAPTER III.

Of the falivary glands.

AROTIS, or MAXILLARIS SUPERIOR, is the

P largeft of the falivary gland; it is fituate be

hind the lower jaw, under the ear; its excretory duct paffes over the upper part of the maffeter mufcle, and enters the mouth through the buccinator. This gland has its faliva promoted by the motions of the lower jaw. Its duct paffes over the tendinous part of the maffeter muscle, that it may not be compreffed by that muscle, which would obftruct the faliva in it, though it is frequently faid that it paffes over that muscle that it may be compreffed by it, to promote the faliva. In fheep, horfes, &c. whofe jaws are long, this mufcle is inferted far from the centre of motion, that the end of the jaw may be moved with fufficient ftrength, and that distant infertion requiring a greater length of muscle, that its motion may be quick enough, no part of this muscle could be allowed to be tendinous; therefore, it feems, to avoid the inconveni

ence

ence of compreffion from the muscle, the duct in thofe animals goes quite round the lower end of it. When this duct is divided by an external wound, the faliva will flow out on the cheek, unless a convenient perforation be made into the mouth, and then the external wound may be healed. I have feen patients with this gland ulcerated, from which there was a conftant effufion of faliva, 'till the greatest part of the gland was confumed with red mercury precipitate; and then they healed with little trouble. HILDANUS mentions the fame cafe, which for two years had been under the care of a furgeon without fuccefs; and was at last cured by the application of an actual cautery.

MAXILLARIS INFERIOR is fituate between the lower jaw and the tendon of the digastric muscle. Its duct paffes under the mufculus mylohyoideus, and enters the mouth under the tongue, near the dentes inciforii. I was at the opening of a woman who was fuffocated by a tumor which begun in this gland, and extended itself from the fternum to the parotid gland on one fide in fix weeks time, and in nine weeks killed her; it was a true schirrus, and weighed twenty fix ounces. In a man which I diffected, I found a quantity of pus near this gland, and a bundle of matter not unlike hair as large as an hen's egg.

the

SUBLINGUALIS is a small gland fituated under tongue, between the jaw and the ceratogloffus mufcle. In a calf I found feveral ducts of this

gland