SPONGES.
Sponges can also be had at the drug store. They have a tap attached to them to be conveniently removed. They should be soaked in an antiseptic solution for a few minutes before coitus and then introduced into the vagina far up as they can be placed. Some physicians have recommended the use of the cotton plug, instead of the sponge, to be soaked in a solution of three per cent carbolic and glycerine, before the act. The male sperm is destroyed by the weakest solution of carbolic acid. Some of the peasants in Europe use the cotton plug soaked in vinegar for the same purpose and find it satisfactory. In this country a boric acid solution has been used for the same purpose and with satisfactory results. Of course this requires a saturated solution, as, for instance, one teaspoonful of the powder to a cup of water stirred until dissolved.
Sponges and plugs can be recommended as perfectly safe, if followed by an antiseptic douche before the removal of the plug or sponge, thus preventing the sperm from entering the womb. The problem is: to kill the male sperm upon entering the vagina, or to wash it out or to kill it directly afterwards. A weak solution of alum may also be used for cotton plugs and sponges, also carbolated vaseline on plugs.