are hot in the fourth degree; those which provoke sweat abundantly, and thus "cut tough and compacted humours" (Culpepper) are hot in the third degree. Opium was cold in the fourth degree, and therefore should only be given alone to mitigate violent pain. In ordinary cases it is wise to moderate the coldness of the opium by combining something of the first degree of cold or heat with it.
An amusing illustration of the reverence which this doctrine of the temperatures inspired is furnished by Sprengel in the second volume of his History of Medicine. Dealing with the Arab period, he tells us that Jacob-Ebn-Izhak-Alkhendi, one of the most celebrated authors of his nation, who lived in the ninth century, and cultivated mathematics, philosophy, and astrology as well as medicine, wrote a book on the subject before us, extending Galen's theory to compound medicines, explaining their action in accordance with the principles of harmony in music. The degrees he explains progress in geometric ratio, so that the fourth degree counts as 16 compared with unity. He sets out his proposition thus: x = bn-1a; a being the first, b the last, x the exponent, and n the number of the terms. Sprengel has pity on those of us who are not familiar with mathematical manipulations, and gives an example to make the formula clear.
Medicament. Weight. Hot. Cold. Humid. Dry.
Cardamoms 3i 1 1/2 1/2 1
Sugar 3ii 2 1 1 2
Indigo 3i 1/2 1 1/2 1
Myrobalans 3ii 1 2 1 2
—- - - —- —-
3vi 4-1/2 4-1/2 3 6
This preparation therefore forms a mixture exactly balanced in hot and cold properties, but twice as dry as
