pe of air.
The engine of Napier and Rankine, patented in the United States, September 19, 1854, and in England June 9, 1853, is of this class.
4. The fourth class includes those which use steam to lubricate the parts; an example will be given, but it is not to be inferred that it is confined to one.
The immense expenditure of grease has induced the use, in many or perhaps most of the airengines, of moistened air as suggested by Glazebrook 1797, Oliver Evans about the same time, and by Bennet 1838.
Bickford, June 6, 1865.
The air is compressed in the reservoir by an annular piston; entering at the valve D during the down stroke, and passing through the piston during the up stroke.
It is moistened by passing through a body of water B before reaching the compressed-air reservoir A. See Aero-steam engine.
5. Of the fifth class is the patent of shearer, September 3, 1861; in which two cylinders are used with two pistons, the faces of which are in co
g two plows to one stock, or two stocks framed together so as to have but one pair of handles and be operated by one man, is mentioned by Walter Blythe, who wrote during the protectorate of Oliver Cromwell.
1. (Electricity.) An instrument to increase the least conceivable quantity of electricity by continually doubling it, until it becomes perceptible upon a common electrometer or is made visible in sparks.
It was first invented by Bennet, improved by Darwin, and afterwards by Nicholson.
See Journal of the telegraph, Vol.
VI., No. 1, December 2, 1872.
2. (Distilling.) A part of the still apparatus, or an appendage to a still in which the low wines, one of the products of the first distillation, are re-distilled.
The operation is a turning back and repeating, and is known as doublig. A part of the still is arranged to condense and then intercept and return the less volatile vapors, while those of greater tenuity pas