Although the majority of brushes are still made by hand, yet a few most ingenious machines have been made which greatly facilitate and speed the operation, and many mechanical appliances have been invented in aid of hand-work. These machines and appliances, together with those which cut, turn, bore, smooth, and polish the handles and backs, to which the brush part is secured, have greatly changed and improved the art of brush-making during the last fifty years. The first machine which attracted general attention was invented by Oscar D. and E. C. Woodbury of New York, and patented in 1870. As in hand-making and before subjected to the action of the machine, the bristles are sorted as to length and color. A brush-back, bored with holes by a gang of bits, which holes do not extend, however, all the way through the back, is placed in the machine under a cone-jointed plunger, adapted to enter the hole in the brush-back. A comb-shaped slitted plate in the machine has then each slit filled with bristles, sufficient in number to form a single tuft. When the machine is started, the bristles in a slit are forced out therefrom through a twisted guideway, which forms them into a round tuft, and which is laid horizontally beneath a plunger, which, descending, first doubles the tuft, and as the plunger continues to descend, forces the double end down into the hole. The plunger is supplied with a wire from a reel, turns as it descends, and twists the wire around the lower end of the tuft, the wire being directed in that way by a spiral groove within the plunger. The continuing action of the plunger is such as to screw the wire into the back. The wire is cut when the rotary plunger commences its descent, and when the tuft is thus secured the plunger ascends, the block is moved for another hole, and another set of bristles is presented for manipulation. Brushes with 70 holes can be turned out by this machine at the rate of one a minute. Another most ingenious machine for this purpose is that of Kennedy, Diss, and Cannan, patented in the United States in 1892. In this, brush blocks of varying sizes, but of the same pattern, are bored by the same machine which receives the bristles, and the tufts are inserted as fast as the holes are bored. Both machines are automatic in operation. _Street-sweeping machines_ began to appear about 1831 in England, shortly after in France, and then in cities in other countries. The simplest form and most effective sweeper comprises a large cylinder armed with spiral rows of splints and hung diagonally on the under side and across a frame having two or four wheels. This cylinder is connected by bevelled gearing with the wheels, and in revolving throws the dirt from the street into a ridge on one side thereof, where it is swept into heaps by hand sweepers, and is then carted off. King of the United States was the inventor.