Zoonomia; Or, the Laws of Organic Life, Vol. II

by Erasmus Darwin

[4]. Risus sardonicus. A disagreeable smile attends inflammations of the diaphragm arising from the associations of the reiterated exertions of that muscle with those of the lips and cheeks in laughing. See Diaphragmitis, Class [II. 1. 2. 6].

[5]. Salivæ fluxus cibo viso. The flow of saliva into the mouths of hungry animals at the sight or smell of food is seen in dogs standing round a dinner-table. The increased actions of the salivary glands have been usually produced by the stimulus of agreeable food on their excretory ducts during the mastication of it; and with this increased action of their excretory ducts the other terminations of those glands in the capillary arteries have been excited into increased action by the mutual association of the ends of canals; and at the same time the pleasurable ideas, or sensual motions, of the sense of smell and of sight have accompanied this increased secretion of saliva. Hence this chain of motions becomes associated with those visual or olfactory ideas, or with the pleasure, which produces or attends them.

[6]. Tensio mamularum viso puerulo. The nipples of lactescent women are liable to become turgid at the sight of their young offspring. The nipple has generally been rendered turgid by the titillation of the lips or gums of the child in giving suck; the visible idea of the child has thus frequently accompanied this pleasurable sensation of parting with the milk, and turgescence of the tubes, which constitute the nipple. Hence the visual idea of the child, and the pleasure which attends it, become associated with those increased arterial actions, which swell the cells of the mamula, and extend its tubes; which is very similar to the tensio phalli visâ muliere nudâ etiam in insomnio.

[7]. Tensio penis in hydrophobia. An erection of the penis occurs in the hydrophobia, and is a troublesome symptom, as observed by Cœlius Aurelianus, Fothergill, and Vaughn, and would seem to be produced by an unexplained sympathy between the sensations about the fauces and the penis. In men the hair grows about both these parts, the voice changes, and the neck thickens at puberty. In the mumps, when the swellings about the throat subsides, the testicles are liable to swell. Venereal infection received by the penis is very liable to affect the throat with ulcers. Violent coughs, with soreness or rawness about the fauces are often attended with erection of the penis; which is also said to happen to male animals, that are hanged; which last circumstance has generally been ascribed to the obstruction of the circulation of the blood, but is more probably occasioned by the stimulus of the cord in compressing the throat; since if it was owing to impeded circulation it ought equally to occur in drowning animals.

In men the throat becomes so thickened at the time of puberty, that a measure of this is used to ascertain the payment of a poll-tax on males in some of the islands of the Mediterranean, which commences at puberty; a string is wrapped twice round the thinnest part of the neck, the ends of it are then put into each corner of the mouth; and if, when thus held in the teeth, it passes readily over the head, the subject is taxable.

It is difficult to point out by what circumstance the sensitive motions of the penis and of the throat and nose become associated; I can only observe, that these parts are subjected to greater pleasurable sensations than any other parts of the body; one being designed to preserve ourselves by the pleasure attending the smell and deglutition of food, and the other to ensure the propagation of our species; and may thus gain an association of their sensitive motion by their being eminently sensible to pleasure. See Class [I. 3. 1. 11]. and [III. 1. 1. 15]. and Sect. XVI. 5.

In the female sex this association between the face, throat, nose, and pubis does not exist; whence no hair grows on their chins at the time of puberty, nor does their voices change, or their necks thicken. This happens probably from there being in them a more exquisite sensitive sympathy between the pubis and the breasts. Hence their breasts swell at the time of puberty, and secrete milk at the time of parturition. And in the parotitis, or mumps, the breasts of women swell, when the tumor of the parotitis subsides. See Class [I. 1. 2. 15]. Whence it would appear, that their breasts possess an intermediate sympathy between the pubis and the throat; as they are the seat of a passion, which men do not possess, that of suckling children.

[8]. Tenesmus calculosus. The sphincter of the rectum becomes painful or inflamed from the association of its sensitive motions with those of the sphincter of the bladder, when the latter is stimulated into violent pain or inflammation by a stone.

[9]. Polypus narium ex ascaridibus? The stimulation of ascarides in the rectum produces by sensitive sympathy an itching of the nose, as explained in [IV. 2. 2. 6]; and in three children I have seen a polypus in the nose, who were all affected with ascarides; to the perpetual stimulation of which, and the consequent sensitive association, I was led to ascribe the inflammation and thickening of the membrane of the nostrils.

[10]. Crampus surarum in cholera. A cramp of the muscles of the legs occurs in violent diarrhœa, or cholera, and from the use of too much acid diet in gouty habits. This seems to sympathize with uneasy sensation in the bowels. See Class [III. 1. 1. 14]. This association is not easily accounted for, but is analogous in some degree to the paralysis of the muscles of the arms in colica saturnina. It would seem, that the muscles of the legs in walking get a sympathy with the lower parts of the intestines, and those of the arms in variety of employment obtain a sympathy with the higher parts of them. See Cholera and Ileus.