New Knapp Battery

A New Carbon Battery.

Probably the three most important points in a primary battery are low internal resistence, high electromotive force and long life. The Knapp Electrical Works, of Chicago, have recently placed on the market a cell combining, they believe, all these requisites, and they have aptly termed it the Chicago carbon battery. They claim that it is the most perfect one made for open circuit work. In addition to the above enumerated points the manufacturers claim that this cell has many other features that add to its value. As will be seen by the cuts shown on this page, the carbon surface presented to the action of the fluid is unusually large, the oval-shaped carbon element being 3 X 4 x 5 1/2 inches in size. The binding post is so attached that no corrosion can take place, nor can the zinc be affected in that manner, the manufacturers claim, as the zinc rod is held in position by an insulating plug fitted so tightly in the cover that neither air nor water can pass through.

The cell proper consists of three parts; the glass jar, the carbon, and the zinc and plug. When set up ready for service the cover fits so perfectly that the jar is practically sealed, and no perceptible evaporation takes place. Thus the cell will probably require no attention for from two to three years, depending on the amount of work performed. The sal ammoniac sent out with these cells is of an unusually high grade, the proper amount being carefully packed in small boxes.

Figs. 1 and 2. — the "Chicago" Carbon Battery.