The humours had different characters. The blood was naturally hot and humid, the phlegm cold and humid, the bile hot and dry, and the black bile cold and dry. Alterations of the humours would cause diseased conditions; distempers was the appropriate term. There might be a too abundant provision of one or more of the humours. A plethora of blood would cause drowsiness, difficulty of breathing, fatty degeneration. A plethora of either of the other humours would have the effect of causing corruption of the blood; plethora of bile, for example, would result in a jaundiced condition, bad breath, a bitter taste in the mouth, and other familiar symptoms. Hæmorrhoids, leprosy, and cancer might result from a plethora of the melancholic humour; colds, catarrhs, rheumatisms were occasioned by a superabundance of the phlegm.
It must not be supposed that Galen or any other authority pretended that the humours were the sole causes of disease. Ancient pathology was a most complicated structure which cannot be even outlined here. The theory of the humours is only indicated in order to show how these explained the action of drugs. To these were attributed hot, humid, cold, and dry qualities to a larger or less extent. Galen classifies them in four degrees—that is to say, a drug might be hot, humid, cold, or dry in the first, second, third, or fourth degree. Consequently the physician had to estimate first which humour was predominant, and in what degree, and then he had to select the drug which would counteract the disproportionate heat, cold, humidity, or dryness. Of course he had his manuals to guide him. Thus Culpepper tells us that horehound, for example, is “hot in the second degree, and dry in the third”; herb Trinity, or pansies, on the other hand, “are cold and moist, both herbs and flowers”; and so forth. Medicines which applied to the skin would raise a blister, mustard, for example, 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 | ʒi | 1 | ½ | ½ | 1 |
| Sugar | ʒii | 2 | 1 | 1 | 2 |
| Indigo | ʒi | ½ | 1 | ½ | 1 |
| Myrobalans | ʒii | 1 | 2 | 1 | 2 |
| ʒvi | 4½ | 4½ | 3 | 6 |
This preparation therefore forms a mixture exactly balanced in hot and cold properties, but twice as dry as it is humid; the mixture is therefore dry in the first degree. If the total had shown twelve of the dry to three of the humid qualities, it would have been dry in the second degree. When it is remembered that in addition to these calculations the physician had to realise that drugs adapted for one part of the body might be of no use for another, it will be perceived that the art of prescribing was a serious business under the sway of the old dogmas.
The Rosicrucians.
It has never been pretended, so far as I am aware, that the Rosicrucian mystics of the middle ages did anything for the advancement of pharmacy. They are only mentioned here because they claimed the power of curing disease, and also because it happens that the fiction which created the legends concerning them was almost contemporaneous with the not unsimilar one (if the latter be a fiction) which made a historical figure of Basil Valentine. Between 1614 and 1616 three works were published professing to reveal the history of the brethren of the Rosy Cross. The first was known as Fama Fraternitatis, the second was the Confessio Fraternitatis, and the third and most important was the “Chymical Marriage of Christian Rosencreutz.” The treatises are written in a mystic jargon, and have been interpreted as alchemical or religious parables, though vast numbers of learned men adopted the records as statements of facts. It was asserted that Christian Rosencreutz, a German, born in 1378, had travelled in the East, and from the wise men of Arabia and other countries had learnt the secrets of their knowledge, religious, necromantic, and alchemical. On his return to Germany he and seven other persons formed this fraternity, which was to be kept secret for a hundred years. The brethren, it is suggested, communicated to each other their discoveries and the knowledge which had been transmitted to them to communicate with each other. They were to treat the sick poor free, were to wear no distinctive dress, but they used the letters C.R. They knew how to make gold, but this was not of much value to them, for they did not seek wealth. They were to meet once a year, and each one appointed his own successor, but there were to be no tombstones or other memorials. Christian Rosencreutz himself is reported to have died at the age of 106, and long afterwards his skeleton was found in a house, a wall having been built over him. Their chief business being to heal the sick poor, they must have known much about medicine, but the books do not reveal anything of any use. They acquired their knowledge, not by study, but by the direct illumination of God. The theories—such as they were—were Paracelsian, and the fraternity, though mystic, was Protestant.
The most curious feature of the story is that the almost obviously fictitious character of the documents which announced it should have been so widely believed. Very soon after their publication German students were fiercely disputing concerning the authenticity of the revelations, and the controversy continued for two hundred years. Much learned investigation into the origin of the first treatises has been made, and the most usual conclusion has been that they were written by a German theologian, Johann Valentin Andreas, of Württemberg, b. 1586, d. 1654. He is said to have declared before his death that he wrote the alleged history expressly as a work of fiction.