&c.
PUMP FOR USE IN CHEMICAL, PAPER, and other Works. The Perreaux Pump Valve is made of vulcanised india rubber, and is of the form of the valves in the human body. It is of the greatest, and perhaps the really only valuable improvement in valves applicable, equally, to the common hand or jack pump, and the most elaborate mechanical combinations for raising water.
The valve may be taken as the key of the pump; a perfect valve renders an indifferent pump a valuable and effective machine, whereas an imperfect valve, in an otherwise excellently constructed pump, renders it practically useless.
The pump which Simon the tanner, of Joppa, used for pumping his pits, nearly two thousand years ago, may be taken as the type of the common hand pump in use to this day. Various mechanical improvements have been made in its form and construction, but, practically, and effectively, the only real and valuable improvement is the Perreaux valve, now under consideration.
Constructed of a flexible material, and made in form, as nearly as may be, to the valves of the human body, they may be said to be automatic in their action, or self acting; upon the pump being actuated, the least motion of the pump ensuring a corresponding action of the valve, and the most rapid action of the pump, being equally responded to by the pulsation of the valves.
Although the most perfect valves for pumping clear water, because, what is mechanically termed the duty of the pump is complete, in other words, the quantity displaced is discharged, absolutely without loss, yet their most valuable feature is that they pump semi-fluids equally well as clear water.
For the pulps and stuffs in paper mills, for bleaches, dyes, and corrosive liquors, for liquid manures and other such semi-fluids, they stand alone, they are absolutely unchokable.
Used in conjunction with cylinders or barrels made of toughened glass, they form the most perfect pump where the fluid to be raised is of a caustic or corrosive nature, and where the fluid would be destructive to or destroyed by its action upon metals, such for example as the caustic bleach used in the manufacture of paper, &c. See Valves.
PUNCH. An acidulous, intoxicating beverage, composed of water sweetened with sugar, with a mixture of lemon juice and spirit, to which some aromatic, as nutmeg, mace, or cinnamon, is occasionally added. Wine is sometimes substituted for spirit. It is much less drunk than formerly. Rum punch is the most popular amongst sailors, who are now the principal consumers of this beverage.
Prep. 1. Juice of 3 or 4 lemons; yellow peel of 1 lemon; lump sugar, 3⁄4 lb.; boiling water, 31⁄2 pints; infuse 1⁄2 an hour, strain, and add, of bitter ale, 1⁄2 pint; rum and brandy, of