This type of pump is, however, not very efficient, for there is not only leakage about the valves and between the piston and cylinder, but at a certain degree of exhaust the air within the vessel is insufficient to raise the inlet valve; this last defect has been met in some measure by using an extension of the piston to open and close the valve.
The inlet pipe enters an elliptical vessel which communicates with the cylinder a little way up from its base, whilst at the base there is a relief tube leading into the elliptical vessel already mentioned.
ZUIDER ZEE, or Zuyder Zee, a land-locked inlet on the coast of Holland, bounded N.
This island separates the Gulf of Taranto from the deep inlet of the Mare Piccolo, and is sheltered by two other flat islands, San Pietro and San Paolo; the latter is occupied by a lighthouse.
From the English Channel, at the head of an inlet or estuary which receives only small streams, on a sharply sloping site.