(From con-gelo, to freeze). Frozen or frost bitten. Persons thus affected by the cold are compared to cataleptic patients, but still there is much difference between the diseases.

When a man is benumbed with cold, and he attempts to warm himself at the fire, the parts exposed to the heat are painful, and a mortification is the general consequence. Thus frozen fruit, if put into water nearly freezing, recovers; but in warm water, or in a warm place, soon rots. Those who are severely affected with cold, should first put the frozen part into cold water, or cover it with snow; and next into water somewhat above the freezing point, until a sense of warmth is perceived, or some degree of motion returns. At this time a little warm wine, mixed with camomile tea, may be drunk, and the warmth gradually increased. A mortification will be in this way avoided.

When travellers begin to be drowsy in the cold, they should redouble their speed to extricate themselves from danger; for though their sleepiness is urgent, it is always fatal.

The heat of our bodies, when in health, very commonly exceeds that of the ambient air: a considerable degree of cold is consequently required to freeze our fluids, and the extremities are the first affected, as most distant from the centre. When a mortification from cold approaches, the part affected by it is first pale, then red: this redness is attended with a troublesome pain and a violent itching; after which the colour becomes almost purple, and at last black.

In these cases, the parts, by their sedative powers of the cold, are deprived of life; or at least their irritability is suspended, and consequently accumulated. Should heat be applied, the excessive action, which is the consequence, soon induces mortification, that would otherwise be avoided. By introducing the heat gradually, the accumulated irritability is sufficient to restore the life of the part. When gangrene has actually taken place, the increased action of the vessels, as usual in such instances, is excited to separate the morbid from the sound part. There is not the slightest evidence, that the organic structure is destroyed by the expansion of the fluids during congelation.

See Tissot's Advice to the People; Van Swieten's Com. on Boerh. Aph. 422, 427, 454; Med. Mus. vol. i. p. 71.