1may happen to be betwixt the contigu
ous ſurfaces of the internal parts of the
Stop-cock: And partly that it may be
the more eaſie to turn the Key (S) back
wards and forwards. Pretty ſtore of oyl
muſt alſo be pour'd into the Cylindre,
both that the Sucker may ſlip up and
down in it the more ſmoothly and freely,
and that the Air might be the better
hindred from getting in between them:
And for the like reaſons, a little oyl is to
be uſed alſo about the Valve. Upon
which occaſion, it would not be omitted
(for it is ſtrange) that oftentimes, when
neither the pouring in of water, nor even
of oyl alone, prov'd capable to make the
Sucker move eaſily enough in the Cylin
der; a mixture of both thoſe Liquors
would readily (ſometimes even to admi
ration) perform the deſired effect. And
laſtly, the braſs cover of the Receiver,
being put into the braſs ring formerly de
ſcrib'd, that no Air may get between
them, it will be very requiſite to plaiſter
over very carefully the upper edges of
both, with the plaiſter formerly mention
ed, or ſome other as cloſe, which is to be
ſpread upon the edges with a hot Iron;
that being melted, it may run into and
ous ſurfaces of the internal parts of the
Stop-cock: And partly that it may be
the more eaſie to turn the Key (S) back
wards and forwards. Pretty ſtore of oyl
muſt alſo be pour'd into the Cylindre,
both that the Sucker may ſlip up and
down in it the more ſmoothly and freely,
and that the Air might be the better
hindred from getting in between them:
And for the like reaſons, a little oyl is to
be uſed alſo about the Valve. Upon
which occaſion, it would not be omitted
(for it is ſtrange) that oftentimes, when
neither the pouring in of water, nor even
of oyl alone, prov'd capable to make the
Sucker move eaſily enough in the Cylin
der; a mixture of both thoſe Liquors
would readily (ſometimes even to admi
ration) perform the deſired effect. And
laſtly, the braſs cover of the Receiver,
being put into the braſs ring formerly de
ſcrib'd, that no Air may get between
them, it will be very requiſite to plaiſter
over very carefully the upper edges of
both, with the plaiſter formerly mention
ed, or ſome other as cloſe, which is to be
ſpread upon the edges with a hot Iron;
that being melted, it may run into and