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Those who assert that it is impossible for a body to sweat blood are not acquainted with the facts. The possibility of this phenomenon was known to the ancients. Thus Apollonius of Rhodes (Third Century B.C.) refers to the bloody sweat as an extraordinary phenomenon, and Aristotle in his Historia Animalium (III, 19) says this:

If the blood gets exceedingly liquid, animals fall sick; for the blood then turns into something like ichor, or a liquid so thin that it at times has been known to exude through the pores like sweat.

And if one will take the trouble to consult a modern medical dictionary under hemathidrosis or hematidrosis, reference will be found to the phenomenon. Thus in The American Illustrated Medical Dictionary (1947, Phila.) we find this entry:

Hematidrosis—The sweating of blood or of fluid mixed with blood. In Taber's Cyclopedic Medical Dictionary (1955, Phila.) occurs this reference:

Hemathidrosis, hematidrosis—Condition of sweating blood.

In a much older medical work we find this interesting note:

Haematidrosis is a functional disturbance of the sweat apparatus whereby blood, through diapedesis into the coils and ducts from their surrounding vascular plexus, becomes mingled with the sweat and appears with it upon the normal skin, producing the phenomenon of so-called "bloody sweat." It is an exceedingly rare occurrence, ....

Thus it is clear that the sweating of blood can occur, even if rarely.

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