The manufacture of the Mackintosh cloth is a singular one. The material is merely two layers of cotton cemented with liquid India-rubber; but the junction is so well effected, that the three become to all intents and purposes one. The stout and well-woven cloth is coiled upon a horizontal beam, like the yarn beam of a loom; and from this it is stretched out in a tight state and a nearly horizontal position. A layer of liquid or rather paste-like solution is applied with a spatula, to a considerable thickness, and the cloth is drawn under a knife edge, which scrapes the solution and diffuses it equally over every part of the cloth, which may be thirty or forty yards long. The cloth is then extended out on a horizontal framework to dry; and, when dried, a second coating is applied in a similar way; and a third and fourth may be similarly applied if necessary. Two pieces, thus coated, are next placed face to face with great care, to prevent creasing or distortion; and, being passed between two smooth wooden rollers, they are so thoroughly pressed as to be made to unite durably and permanently. Cloth, thus cemented and doubled and dried, may be cut and made into garments which will bear many a rough trial, and many a deluging before rain or water can penetrate. INDIA-RUBBER CUTTING PROCESSES. It is as a _sheet_ and as a _thread_ that India-rubber meets its most extensive application; and both of these are made by cutting from the blocks and slabs. A block is cut into sheets by an ingenious machine, in which a sharp knife-edge has a rapid vibratory motion in a horizontal plane, so adjusted as to cut a thin film from a block of India-rubber supplied to it by a steady motion. The knife requires to be kept cool by a flow of water, or it would adhere to the India-rubber. In this way thin sheets may be cut, or thicker sheets from which stationers’ India-rubber may be obtained, or sheets of any thickness, great or small, according to the purposes required.