228

Muschenbroeck’s Pump.

[Book II,

it f'ormed a part, served as a fulcrum on which the rod and handle (both ofone piece) moved. The rod was curved so as to move in the centre ofthe chamber.

No. 93. Curved Pump.

The objects supposed to have been attained bj this arrangement, were“ greater simplicity of workmanship,” and “ greater steadiness and preci-sion of action” (of the sucker.) The device is ingenious, but can never begenerally adopted. The spring of the rod with the wear of the bolt onwhich it turns, must soon render the play of the sucker and wear of the ,chamber unequal: the difficulty and expense of making the latter curvi-linear, and of repairing it when bruised or otherwise injured, are fatalobjections. The pipe must be separated from the chamber to get at the

lower box or valve; and the applieationof the pump is limited to depths within30 feet. We have noticed it, lest thesame idea occurring to some of our me-chanics, should lead them to a uselessexpenditure of time and money. In thesame year a patent was issued in Eng-land for making the eylinder in the formof a ring, or nearly so, the centre ofwhich was the fulcrum on which the pis-ton turned, and an alternating motionwas imparted to the latter. Repertoryof Arts, vol. xxxv. 1819.

An interesting modification of the at-mospheric pump was described by Mus-chenbroeck in his Natural Philosophy .Instead of a piston or sucker workinginside of the eylinder, the latter itself ismoved, being made to slide over the pipesornewhat in the manner of tefescopetubes. No. 94 represents this pump.The upper end of the suction pipe, beingmade of copper or brass, and its exte-rior smooth and straight, is passedthrough the bottom of a small cistern. Its orifice is closed by a valveopening upwards. A short eylinder whose diameter exceeds that of thesuction pipe is slipped over the latter; and to its lower end a stuffing boxis adapted to prevent air or water from passing between them. Its upper

No. 94. Muschenbroeck’s Pump.