A Providence, R. I., paper gives the following description in part of the trial of a new aerial truck recently given in that city: “The demonstration of the new automatic aerial hook and ladder truck, built by the Combination Ladder Company of this city, of which Charles N. Richardson is proprietor, was witnessed this afternoon in front of the Central fire station on Exchange place by several hundred citizens. The new truck was put through all the manoeuvers which will be later called into play by the city’s fire fighters in battling with the flames. Many firemen, who were off duty at the time, witnessed the demonstration. Equipped with the newest type of trussed ladders throughout, a 75-foot automobile aerial compound spring hoist, the aerial hoist ladders are automatic, safe and positive of instant control at all angles; the turntable is so construtted that it may be swung with ease in full view of the operator from the ground. Two men on the ground may easily lower the ladder, and it is so constructed that when the ladder is fully lowered the gears are automatically disengaged. In addition to the aerial ladder the truck is equipped with 249 feet of service ladders. All ladders are equipped with the Providence automatic safety locks, and the proper tools are installed on the machine. A new and improved worm and gear type of rear steering wheel gives a wide steering radius. At all times the truck is in absolute control, at all speeds, of the operator, by means of improved automobile brakes of the latest design.” Following is an explanation of the automatic aerial ladder spring hoisting device: The raising device on the Providence aerial truck has many distinctive features. First: Because, as herein described, it shows itself to be simple and effective. Secondly: No segments or gear wheels to raise the ladder are used. Thirdly: The ladder is raised by more powerful springs and control the action of said springs positively and quickly by an entirely new method of governing not depending upon air liquid or screw as a governing principle. The method being as follows: To elevate the aerial ladder, it is only necessary to release by hand lever the clutch attached to cross shaft at front of turntable by means of which ladder is held in place; the expansion of the springs then elevates the main ladder in four seconds time, said ladder in its elevating being under perfect control of operator by means of hand lever attached to a powerful internal expanding band brake placed near heel of ladder mounted directly upon the hub encircling eccentric shaft, an entirely new and most powerful method of control applied more quickly and easily than any other known principle. To lower the ladders are bevel gears mounted on a shaft running cross-ways at the end of the cylinders operated by cranks. The governing power being entirely removed from the screw and all control being vested as desbribed by the above methods. The advantage here is plainly to be seen. Inasmuch as the direct control down on an exact level with springs does away with the great friction or loss of power when a screw governor is used to govern the ladder far above the base of the power; consequently the ladder will operate more easily and quickly and steadily. Arms upon each side of a screw attached to a traveling nut run back and are attached to the cross head of the plungers which are pushed out by the springs automatically, as the ladder raises. There is in the end of each tube an adjusting screw. This screw is to be taken up or let out on the springs to insure the exact pressure necessary to raise the ladder. This adjustment is made on the outside with a wrench furnished for this purpose. By these principies all whipping of the main ladder is stopped, inasmuch as the spring action is directly controlled, there being no lost motion or friction.

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