The Locomotive Of Today

The Tender, Brakes, etc. : Water Scoop and Gear. 169 engine is running—will only take water, the other simply follows in the wake of the first. A flap or hinged valve at the junction of the scoops with the casting closes the way by which the water could otherwise escape. When the engine runs in the reverse direction of course the other scoop will take water, and the flap will fail over to the opposite side. . E is an end view of the same engine, showing the branch pipes up which the water passes and enters each side tank simultaneously and in equal quantities. In both these views the scoops are shown raised up in the carrying position ; a balance weight is fitted, as before, to hold the scoops safely in this place. An enlarged section of the cylinder and diaphragm is shown at F. The top and bottom of it are each made of a dished form, provided with flanges which face each other where they are bolted together; the diaphragm is of india- rubber, or other suitable material, stiffened at the centre by the piston head above and plate below. Bosses, for the con- nection of the pipes to top and bottom of the cylinder, are provided. The piston rod which reaches down to the scoop is not fitted with a stuffing box but a large flexible hose securely fastened at top and bottom covers it; this prevents the access of air to the bottom end when a vacuum is formed, but allows full freedom for the rod to rise and fali with the piston head. At G the actuating cock is drawn to the same large scale as the cylinder. The cock casting has three unions to it, for the attachment of three pipes, one from the vacuum chamber and one from top and bottom of the cylinder respectively. The plug in the cock is chambered out, so that by giving it a partial revolution it is possible to put either end of the cylin- der in communication with the vacuum chamber, the opposite end of the cylinder at the same time being opened to the atmosphere; when turned to a position midway between the extremes, the holes are all closed. The three positions of the plug are shown below and at the right of the figure. The water troughs are usually made of Steel plate bent to the required shape in lengths and rivetted together; they are about 18-ins. wide by 6-ins. deep placed upon the sleepers and supported at the sides upon baulks of timber. The level of the top of the trough is about 3-ins. above that of the top of the rail, and the water line 2-ins. above the rail. The scoop, when down, dips into the water about 2-ins., being then at the rail level. The total length of the trough may vary, according to the quantity of water it is required to take, but it is usually about 500 yards long, with ends which gradually taper out.