The French Letter is the only preventive which diminishes a great deal the chances of contracting venereal diseases.
When there is any chance of venereal contagion, it is necessary to wash the French Letter with a solution of corrosive sublimate (perchloride of mercury), one in 10,000 parts of water; then it should be dried and powdered. By using this solution immediately after connection, it is seen at once whether the French Letter has been torn; in this case, the man must wash himself, and the woman should use an injection with the same solution, not only to prevent contagion to both of themselves, but she also to prevent the birth of an infected infant.
When the husband is drunk, and his wife, fearing that a miserable child will be born, has no other preventive at hand, she can perhaps apply the French Letter as if caressing him, when he does not know what he is doing. At all events, she should always take care that one or two French Letters be ready for use.
The wife may prevent conception by passing into the vagina the _occlusive pessary_ of _Dr. Mensinga_; if this do not remain in its place, she may rather use that named _Matrisalus_, which is more curved. If this also does not remain in its place, the husband should use the French Letter or condom. If, finally, the husband will not use these means, the wife may use the _tubular pessary_, or, for want of a better, the _sponge_. (This is the only method available in countries where there are no medical practitioners or other persons who know the business, and can choose and teach women how to place the pessaries.)
These instruments, designed to cover the mouth of the womb, are not worn in the daytime. The wife may introduce them every evening (and by preference before the return of her husband). During the night they all may remain untouched, unless there be danger of the instrument being ill-placed. On the morrow, or in uncertain cases immediately after connection, a small injection should first be made, in order to cleanse away the greater part of the sperm, then the instrument should be withdrawn standing upright or kneeling; finally a full injection should be made use of to clear out thoroughly every corner of the organ. The pessary must then be cleaned carefully, and inspected to see that it is in good condition, wiped gently and put away in a drawer without wrapping it up.