EQUALIZER. An apparatus for equal izing the propelling power of steam en gines and other prime movers. Various contrivances have been employed for this purpose, more especially with engines working steam expansively, where a fluc tuation in the pressure of the impelling medium affects the uniformity of the motion of the main shaft. Among the best appliances of this kind may be ncm ticed the Power Regulator, recently pat ented by Alfred Gregory, of New York. It consists of a small piston working within a cylinder which is open at one end to the steam in the boiler, and—if the engine is of the condensing kind—at the other end to the vacuum of the con denser. This piston is operated by the engine so as to make two strokes for every one of the engine piston, and is made to act as a drag at the commence ment, and as an auxiliary towards the close of the stroke of the engine piston, and thus to equalize the propelling power, without reference to the period at which the steam may he "cut off." Whatever
may be the fluctuation in the impelling medium, the regulator always produces the same relative effect upon the engine. FELT CLOTH, is cloth produced with out weaving, by crossing the sheets of batting from two carding engines, and then shrinking them until they are closely matted together. A kind of carpet is manufactured in this way, the pattern be ing printed after the fabric is made. GAUGE, in mechanical manipulation, is a term given to all instruments for set ting out distances, or for measuring thickness or calibre, and to almost every device which serves as a guide by which to work out any particular form.%