The habit of injecting cold water into the vagina after connection, to which many women pin their faith, is, like most of the other methods alluded to, of very doubtful efficacy, while of unquestionable danger. It must be bome in mind that the living germ of the male, protected as it is by the dense albuminous medium in which it exists, is practically invulnerable to any such attacks. The water is brought up to the temperature of the blood long before this albuminous covering can be dissolved, or the spermatozoon reached; while the shock occasioned to the delicate sexual organism, by introducing fluids of so low a temperature into the superheated vagina, can hardly fail to produce those various forms of subacute membranous inflammations to which, clinical experience has shown us, persons who indulge the practice are peculiarly subject. And the same objections apply where the water is "medicated" by the various powders so largely sold for the purpose; only that there is greater liability to permanent injury than when water alone is used. Both act only upon the seminal medium—the albuminous vehicle which transmits the germ— not upon the germ itself; and if only one of these little agents survive, out of a thousand, the mischief is done. Thus, when zinc, bichloride of mercury or other toxic agent is injected into the vagina there is coagulation of the albumen, locking up for a brief space, and actually protecting instead of destroying the sperm-cell; but the moment this covering is redissolved— which occurs long within the natural life-period of the germ itself—the latter is liberated, and free to pursue its natural course unhindered.