Obtain a thick iron-wire shank, about two inches long, and inserted into a small wooden handle ; on its extremity, which must be slightly curved, have a disk or button of iron, exactly one-quarter of an inch thick, and half an inch in diameter. The whole instrument to be only six inches in length. The face of the disk for application must be flat.
Mode of Application. — Light a small spirit lamp, and hold the button over the flame, keeping the fore-finger of the hand holding the instrument, at the distance of about half an inch from the button. As soon as the finger feels uncomfortably hot, the instrument is ready for use, and the time required for heating it to this degree, will be about half a minute. It is to be applied as quickly as possible to the parts, the skin being tipped successively, at intervals of half an inch, over the affected part, as lightly and as rapidly as possible, always taking care to bring the flat surface of the disk fairly in contact with the skin. In this way the process of firing a whole limb, or the loins, making about one hundred applications, does not occupy a minute, and the one heating by the lamp suffices. To ascertain whether the heat be sufficient, look sidewise at the spots as you touch them, and each spot will be observed to become of a glistening white, much whiter than the surrounding skin. In from five to thirty minutes the skin becomes bright red, and a glow of heat is felt over the part. The iron must never be made red-hot — it is very little hotter than boiling water — should never make an eschar, and rarely raise a blister. On the next day after its application, a number of circular red marks will be seen on the skin, the cuticle not even being raised, and the surface ready, if necessary, for a fresh application. There is no discharge whatever, and in most cases the patient is unconscious of what has been done. It is vastly superior to a blister in many cases ; even the most delicate female will not object to its frequent repetition when required.
Properties and Uses. — A powerful counter-irritant. Recommended by Dr. Corrigan in paralysis, local muscular rheumatism, sciatica, lumbago, neuralgic pains, etc., and wherever a counter-irritant is required. Also applied each side of the spinal column, in intermittents, epilepsy, mania and other diseases.