Cakuli of the prostate gland are (some times at least) essentially different in nature from urinary calculi, and belong to the class produced by morbid. secretions from mucous surfaces. Sometimes single, they are more generally numerous ; in the latter case, though occasionally found of much greater bulk, they rarely exceed a pea or small nut in size. One variety of prostatal calculus is, according to Dr. Prout, found in the natural cavities of the gland, before this becomes much disorganized ; the calculous masses referable to this variety are of more or less rounded shape and yel lowish-brown colour. Another variety seems to be generally found in an enlarged cavity or abscess of the prostate gland, and sometimes has a highly polished porcellanous appearance. But that this distinction is rather an artificial than a natural one appears from the similarity of composition of both varieties. As first shown by Wollaston, these calculi consist mainly of phosphate of lime and animal matter with carbonate of lime in variable proportions.
Proputial calculi and those found in urinary fistulce belong, in the great majority of cases, to the class of saline masses generated through irritation of mucous (or pseudo-mucous) sur faces, and accordingly consist wholly of earthy phosphates. There is no reason, however, that a particle of gravel, or a minute calculus of various chemical constitutions, might not make its way into these situations, and become the nucleus of further deposit : and in point of fact Romer found uric acid, phosphate of lime, and animal matter in some calculi removed from underneath the prepuce of a child affect ed with natural phymosis. — (b). Lachrymal calcurz.— Calculous forma tions in the lachrymal organs, positively speak ing rare, are much less commonly met with in the gland and its excretory ducts than in the folds of the conjunctiva, in connection with the caruncula or in the lachrymal canals and nasal duct. They may be known by the generic name clacryolith, (from Satcpuov, a tear, and ?An, a stone,) first proposed by Walther.
An example of the actual formation of such calculous masses in the excretory ducts of the gland occurred in the case of a female, aged 19, who came under the notice of Mr. R. H.Meade, (Med. Gazette, 1835.) Twenty-three calculi, of small size, (the largest about a line in dia meter,) rough, very hard, and of dirty white colour, were discharged from-the' ducts in the course of four or five days. They consisted principally of phosphate of lime, with a small quantity of carbonate of the same base and traces of animal matter. Von Walther de scribes a curious case, in which calcareous matter continued to be formed in the folds of the conjunctiva during a space of about ten weeks. The first mass formed was of angular shape, about the size of a pea, and easily ca pable of being rubbed down into a greasy powder. It reappeared in three days ; and sub
sequently a ,similar matter formed in the other eye. The deposition ceased under the use of potash internally, but returned three years after; carbonate of lime chiefly, with phosphate of lime and animal matter, were its constituents. Numerous examples are on record of such concretions occurrina in the follicles of the caruncula. Sandifort,Blegny, Schinucker, Air. Travers, and others have seen calcareous mat ter in the lachrymal canals. Krimer* has de scribed a calculus of the size of' a small pea, of ash-grey colour, polished, of' calcareous ap pearance, removed from the nasal duct of a woman, who for nine months had laboured under disease of the lachrymal passages.
There is a species of calculus, essentially of fatty nature, commonly known as " deer s tears,' which forms in the fosse just below the anterior canthus of the adult red deer (cervus elephas). It yields on analysis resin with ethereal oil, fatty oil, wax, cellular substance, colourim, matter, chloride of sodium, and phos phate oflime. Some of these ingredients are supposed to be derived from hair, which is usually entangled with it. It is said to pos sess the medicinal virtues of the fcetid antispas modics.± (c). Nasal calculi. — Calculous masses are not extremely uncommon in the nares. Some of them are indubitably formed in the lachrymal passages, whence they glide into the nostrils; such was, in all probability, the case with the little girl spoken of by Bartholinus, who forced small calculi from her nose. In other instances they manifestly originate in the nos trils themselves; this is especially certain when the nucleus of the mass consists of a foreign body. Thus Horn found a calculus in the nares, the nucleus of which was a cherry-stone. Grandoni removed from the left nostril of a woman, aged 32, a calculus formed of frag ments of unequal sizes, weighing 76 grains, of a specific gravity of 1.4, without smell, and chemically constituted as follows : — In the largest of the fragments a grass seed was discovered.t (d) _Frontal sinus, calculi of.—Several calculi of small size, consisting of phosphate of lime, carbonates of lime and magnesia, oxide of iron and soda in small quantity, and animal matter, were discharged from the frontal sinus of a woman, whose case will be found in a foreign journal.§ (e.) Mouth, calcurz of.— The interior of the mouth may become the seat of calculous form ation. Schenk, Echold, and Bartholinus re late cases of its occurrence in connection with the mucous membrane of the palate ; Kruger describes a mass of aShen colour, hard, round, and very light, thrown off from an ulcer in the palate. Otto* knew a person in whom, during an atonic attack of gout, the whole mouth, throat, and gullet were largely covered with a whitish mucus [diphtheritic deposit ?j, which contained a large quantity of phosphate of lime.