4. A lancet may be used instead of a needle; and if only scabs are to be had, the scarf skin should be separated from the true skin, and a little of this powdered matter rubbed against it; the raised cuticle is then to be let down again, and pressed with the finger to make it stick to the skin.
5. Whether a needle or a lancet is employed, care must be taken to apply the matter to the live skin, without going through or tearing it.
6. The variolous virus being thus transferred from the needle, thread, or lancet to the live skin, which lies under the cuticle, this last will sufficiently keep it in, and no plaister is ever to be used.
7. The fittest part for insertion seems to be between the thumb and fore-finger, on the outside of the hand. They do it so in India, Syria, Egypt, and Barbary; and it is preferable on many accompts: the hands are always exposed to the air; the inflammation, which the insertion necessarily brings on, is cæteris paribus smaller and less troublesome, where the skin is least stretched, as in this wrinkled part; the insertion is more easily made there than any where else, because the scarf-skin is thicker, and harder to break; and lastly, the symptoms attending the insertion are more easily observed.
8. These advantages, however, are not so considerable as to make one apprehensive of any great risk from the choice of another place.