battery is shown at Fig. 78 and one using batteries of the leadplate type is depicted at Fig. 79. The details of the battery placing and location of propelling machinery are sufficiently clear so the general details may be easily understood. There seems to be considerable difference of opinion relative to the best type of storage battery for submarine work, the advocates of the alkaline battery offering a number of arguments that merit consideration. A typical submarine boat battery cell of the alkaline type is shown at Fig. 80 A, the negative plate at B and the positive plate at C. The general structure is the same as the smaller Edison cells, except that the plates are built up of a number of sub-grids that correspond to the elements of the smaller batteries, riveted to a main frame of sheet steel to form plates of the required capacity. The cells are installed so that they will remain securely in place regardless of the shaking up they receive when the boat is in rough water. The cells are constructed so no electrolyte can escape or water enter. The Edison battery is also built strong enough so gas explosions can take place in its interior without damaging the parts. The illustration at Fig. 78 was furnished by the Edison Storage Battery Company, and shows a proposed design of Lake Torpedo Boat fleet submarine, in which one can see the location of the battery, indicated by "21." It would necessarily be quite a large battery, having a capacity of about 10,000 ampere-hours, at 220 volts. The sectional view at Fig. 81 is a typical coast-defense type of submarine. As described by M. R. Hutchison, E.E., engineering advisor to Thomas A. Edison, the details are: "This is a smaller boat, and is 135 feet long, 14 feet beam. The displacement submerged, 337 tons. Engines, two in number, are about 300 horsepower each. The two propelling motors are about 115 horsepower each, 220 volts. The surface speed is about thirteen knots, submerged speed about nine and one-half knots. The battery would consist of two hundred Edison cells, the total number in each of the tanks being one hundred. The drawing will show the location of the battery tank. The capacity of such a battery would be about 900 kilowatt-hours at the three-hour rate of discharge, and about 540 kilowatt-hours at the one-hour rate of discharge. This capacity would be in excess of the capacity of any lead storage battery installed in the same tank, and would be five or six tons lighter than a lead-sulphuric-acid battery installed in the same tank. This will naturally give the vessel an increased cruising area under water and provide excess capacity, because of the reduction in weight, for fuel oil." The advantages of the Edison battery are given by the same authority as follows: “First, it is the lightest battery, and occupies the least space for a given output of any now obtainable. "Second, its electrolyte is non-corrosive, is not injurious to the steel work of the hold or fittings of the boat. "Third, it cannot cause leaks by corrosion of rivets or joints, no matter how much electrolyte might escape from the cells. |