Care should be taken, when filling the syringe, to express all the air
from it--by filling and refilling it two or three times with the nozzle
under water; otherwise the first thing put into the vagina would not be
warm water or antiseptic lotion, but simply a large bubble of air.

4. _Soluble Suppositories and Rubber Pessaries._--It is quite true that
the use of a suitable soluble suppository alone may be sufficient to
protect against impregnation, but the protection by this means does
undoubtedly fail at times, and therefore, by itself, the soluble
suppository is unreliable. Still it eliminates the majority of the chances
of impregnation. The use of the rubber pessary is also sometimes
unsuccessful because it does not fit properly, or because it is porous, or
because in removing it some of the seminal fluid from the under-surface
may be accidentally spilt in the vagina, and in this way the spermatazoa
may later find their way upwards to an ovum. Therefore, the soluble
suppository and the rubber pessary should be used in combination. A woman
should first push up, as far as possible, a suitable suppository, and then
insert the rubber pessary (slightly soaped--with soap-suds), so as to
occlude the whole of the upper part of her genital passage and thus cover
the mouth of the womb and effectively prevent entrance of the spermatazoa.
The rubber pessary _must_ in the first instance be fitted by a doctor,
because if it does not fit properly it will be ineffective. The seminal
fluid may pass by its loose rim and impregnation may result. If the rubber
pessary has been properly fitted, and _it is not porous_, the protection
should be complete; but if, by any accident, spermatazoa should get beyond
the rubber pessary, they will be destroyed and tangled in the melted
suppository--provided, of course, that a suitable suppository has been
used. It is all a question of getting the right articles to begin with and
using them intelligently. But there is this chance--a bare chance--of
accidental impregnation, and we want to eliminate all chances, if