1911 Encyclopædia Britannica/Cupping
CUPPING. The operation of cupping is one of the methods that have been adopted by surgeons to draw blood from an inflamed part in order to relieve the inflammation. The skin is washed and dried; a glass cup with a rounded edge is then firmly applied, after the air in it has been heated; the cooling of the air causes the formation of a partial vacuum, and the blood is thus drawn from the neighbouring parts to the skin under the cup. Either the blood is drawn from the patient’s body through a number of small wounds which are made in the skin, with a special instrument, before the cup is applied; or the cup is simply applied to the unbroken skin and the blood drawn into the subcutaneous tissue within the circumference of the cup. The result of both methods is the same,—namely, a withdrawal of blood locally from the inflamed part. The former is called moist cupping, the latter dry cupping. This operation has naturally declined in vogue with the obsolescence of blood-letting as a remedy.