=168. Electric Boats= are run by the current from storage batteries which are usually placed under the seats. An electric motor large enough to run a small boat takes up very little room and is generally placed under the floor. This leaves the entire boat for the use of passengers. The motor is connected to the shaft that turns the screw. Fig. 247 shows one design. =169. Electric Automobiles= represent the highest type of electrical and mechanical construction. The _running-gear_ is usually made of the best cold-drawn seamless steel tubing, to get the greatest strength from a given weight of material. The wheels are made in a variety of styles, but nearly all have ball bearings and pneumatic tires. In the lightest styles the wheels have wire spokes. The _electric motors_, supported by the running-gear, are geared to the rear wheels. The motors are made as nearly dust-proof as possible. _Storage batteries_ are put in a convenient place, depending upon the design of the carriage, and from these the motors receive the current. These can be charged from the ordinary 110-volt lighting circuits or from private dynamos. The proper plugs and attachments are usually furnished by the various makers for connecting the batteries with the street current, which is shut off when the batteries are full by an automatic switch. [Illustration: Fig. 247.] _Controllers_ are used, as on electric cars, the lever for starting, stopping, etc., being usually placed on the left-hand side of the seat. The _steering_ is done by a lever that moves the front wheels. Strong brakes, and the ability to quickly reverse the motors, allow electric carriages to be stopped suddenly in case of accidents. Electric automobiles are largely used in cities, or where the current can be easily had. The batteries must be re-charged after they have run the motors for a certain time which depends upon the speed and road, as well as upon the construction. Where carriages are to be run almost constantly, as is the case with those used for general passenger service in cities, duplicate batteries are necessary, so that one or two sets can be charged while another is in use. Fig. 248 shows one form of electric vehicle, the storage batteries being placed under and back of the seat. [Illustration: Fig. 248.] CHAPTER XXVI. A WORD ABOUT CENTRAL STATIONS.