LET there be a vessel containing wine and provided with a spout, underneath which a goblet is placed:
whatever quantity of wine is taken
from the goblet, as much shall flow into it from the spout. Let
A B (fig. 67), be the vessel of wine, and C D the spout, to which are
attached the valve E F, and the rods GH, KL, KO, LM as before;
and beneath the spout place the cup P. To
the rod K 0 fix a small basin R contained in the vessel S T, and let
a tube, U Q, connect the vessels ST and P. When these arrangements are
complete, if the vessels S T and P are empty, the basin a will fall to
the bottom of S T, and open the spout C D. A stream will flow from C D
into both the vessels S T and P, So that the basin will rise and shut
the spout again, until we remove more liquid from the goblet. This
result will happen as often as we remove liquid from P