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the procedure again three or four times, after which the whole barrel is
to be charged with the lotion, and the syringe kept in this condition for
the number of hours prescribed above. The lotion is finally removed
from the syringe just before beginning work.
II.—If the syringe be kept unused for some time, the plunger is apt to dry up
and not to fit the syringe any more ; or, on the contrary, it may stick to the barrel,
and get damaged when attempt is made to open the syringe again. To prevent this,
every time the work is to be interrupted for several days, the metal frame of the
syringe is to be unscrewed, and the glass barrel, with the piston remaining in it,
withdrawn from the frame. A drop of vaseline is then put in front and behind the
plunger, the glass barrel replaced in the metal frame, the latter screwed up again, and
the piston well-oiled with the vaseline by moving it in the barrel several times forward
and backward. Before, however, replacing the barrel into the frame, in case the
syringe bears a leather piston, the leather ring to be found at the bottom of the metal
frame is to be taken out cautiously, so as not to cut or tear it, and turned upside
down : otherwise the syringe will afterwards leak between the glass barrel and the
metal frame. On no account should the piston be withdrawn from the glass barrel
as the operator is liable to damage it, and occasionally to break the barrel, when trying
to replace the piston into the barrel back again. The metal frame is to be screwed
together tightly, but not too much so, as the barrel is apt to crack in a too tight
frame. In some syringes "with rubber plungers in them, an arrangement is made
whereby the plunger can be tightened or loosened without removing the piston from
the barrel. This is done either by turning a screw to be found on the top of the
piston rod ; or, on the contrary, by fixing the screw underneath the plunger, that
keeps it in position, on to a protuberance in the far end of the syringe, and then
turning the piston rod itself. The details will be seen by an inspection of such a
syringe ; attention is only drawn here to that kind of syringe in order that the
operator, by manipulating the screw or piston rod, should not inadvertently tighten
or loosen the plunger beyond the desired degree.
III.—Every time the whole syringe has been unscrewed and opened, it should
afterwards be cleaned and sterilized as if it was a new syringe, that is, by rinsing and
keeping it soaked in carbolic acid for 24 hours, before being used again.
IV.—When the plunger gets in any way damaged, the syringe should bo sent
to the Laboratory for repairs, rather than spare plungers be indented for, as barrels
differ slightly in diameter, and, on the other hand, plungers change in size in this
country, and do not fit the syringe unless specially selected each time.
V.—While filling the syringe with the needle on it from a glass or any other
vessel, it is very essential to avoid even momentary contact between the point of the
needle and the surface of the vessel, as otherwise the point, which is very thin, gets
bent immediately, and the act of injection becomes from that unnecessarily painful
to the patient. But there is no objection in applying to the surface of the vessel
the oblique opening of the needle, which is even recommended when sucking up into
the syringe the last drops of material remaining in the tube or bottlo k
VI.—The plague prophylactic or cholera vaccine should be absorbed into the
syringe directly from the test tube or the bottle in which the fluids are prepared
or supplied ; that is, the material should on no account be poured out, for conveni-
ence sake, into another vessel.
VII.—The bottle or test tube containing the material should always be shaken
anow before absorbing it into the syringe. While filling the syringe, the operator
holds the barrel in his left hand and introduces the needle-, with its oblique-opening