1911 Encyclopædia Britannica/Condenser
CONDENSER, the name given to many forms of apparatus which have for their object the concentration of matter, or bringing it into a smaller volume, or the intensification of energy. In chemistry the word is applied to an apparatus which cools down, or condenses, a vapour to a liquid; reference should be made to the article Distillation for the various types in use, and also to Gas (Gas Manufacture) and Coal Tar; the device for the condensation of the exhaust steam of a steam-engine is treated in the article Steam-Engine. In woollen manufactures, “condensation” of the wool is an important operation and is accomplished by means of a “condenser.” The term is also given—generally as a qualification, e.g. condensing-syringe, condensing-pump,—to apparatus by which air or a vapour may be compressed. In optics a “condenser” is a lens, or system of lenses, which serves to concentrate or bring the luminous rays to a focus; it is specially an adjunct to the optical lantern and microscope. In electrostatics a condenser is a device for concentrating an electrostatic charge (see Electrostatics; Leyden Jar; Electrophorus).