These hooked poles are made of various lengths, ranging from about 10 to 20 feet and more. Some single ladders and extensions reach to over 80 feet; but it will be seen at once that a succession of, say, ten- or twelve-feet hooked-pole ladders can be easily handled to reach from floor to floor, and that, used by an active and well-trained fireman, it can become a most important appliance for saving life. St. Louis appears to have been the pioneer city in the use of this apparatus; but New York and other corporations have followed suit. Since 1883 every candidate for the New York Fire Department must undergo a course of instruction in the use of this and other appliances, and the thorough learning in this work renders them better men for their ordinary duties. The ladders are wheeled to the fire on a truck 50 feet long, and called a "hook-and-ladder truck." It carries ladders of different lengths, and also conveys pickaxes, shovels, battering-rams, fire-extinguishers, life-lines, etc., and tools for pushing open heavy doors. The majority of the ladders are placed on rollers, and can be removed at once without disturbing those resting above them. [Illustration: AMERICAN FIRE-LADDERS.] To some extent, therefore, we might say that the hook-and-ladder truck with its various appliances answers to the horsed escape of the London Brigade; but, while London firemen make use of the escape as a point of vantage whence they can discharge water on the fire, the Americans largely adopt the water-tower. Indeed, they appear to regard this apparatus as indispensable for high business buildings. Briefly, it consists of lengths of pipe, which can be quickly jointed together, the lengths being carried on a van, and varying from about 30 to 50 feet. When jointed, they can rapidly be raised to an upright position, the topmost length having a flexible pipe and nozzle for the discharge of the jet of water. This pipe can be turned in any direction by means of a wire rope descending below, and the tower can be revolved by simple apparatus-gearing. The whole appliance is so arranged that it can be controlled by one man when in action. The water is supplied by a hose fastened to the bottom of the tower. [Illustration: AMERICAN FIRE-LADDERS.] As in England, hydrants are largely used in the States, and the steam fire-engine is also, of course, a very important appliance. The average American steam fire-engine generally weighs about three tons, with water in boiler and men in their seats on the machine. The water in the boiler is kept at steaming-point by a pipe full of steam passing through it, or boiling water is supplied from a stationary boiler, so that on arriving at a fire a working-pressure is obtained. The steam-heating pipe, however, is capable of being instantly disconnected at the sound of the fire-alarm.