prevent the breeding of noxious Humours in the Blood for the future, which may be as dangerous by combining and taking Part with the next Disease, that is stirred up there, this Operation would be of admirable use, but since that is not to be hoped for, I cannot see what Benefit it brings to Mankind. I ask Pardon of the Reader for being so diffusive and copious on this Argument; for I thought it necessary to be so, not only because the Subject is new, but because a thorough Discussion of it sets this Controversy in a true and clear Light.
My second Objection against Inoculation, which was suggested to me by Dr. Wats, a Gentleman of superior Abilities, Integrity, and great Diligence in his Profession, is this, that it is very probable, that the Seeds of other Distempers may be communicated together with those of the Small-Pox, contained in the purulent Matter, taken from the ripe Pustules of the Patient, and Inoculated upon one that never had the Disease. The Principles of Diseases are of the minutest Size, and some of them, that were lodged in the Blood, may well be supposed to adhere to the Matter that produced and fed the Pustules, and still to be contained in the inoculated Matter conveyed to another. It is allowed, that the Principles of the Kings Evil, of Consumptions, Lunacy, and Venereal Diseases, are conveyed from Fathers to their Children successively through many Ge-
