Owen J. Roberts

“ The bottom enclosure is the terminal for one electrode, the top enclosure for the other. The electrolyte is a viscous liquid composed of ammonium chloride, zinc chloride, water and starch. Use of the battery causes erosion of the zinc and eventually the mixture leaks through the container. A short circuit, or long continuous use, causes the formation of solids as the zinc is eaten away. The resultant expansion of the cell contents, due to the weakness of the zinc walls, causes bulging, breaking, and seepage. The escaping liquid tends to injure the metal walls of the flash light casing. ”

“ The patent, a very narrow one in a crowded art, is for a leakproof dry cell for a flash light battery. The conventional dry cell embodies a cup-like zinc electrode acting as a container for a central carbon electrode, electrolyte, and depolarizing mix. ”

“ He states that the object of his invention is to protect the side walls of the zinc cup by providing a strong metal sheath which will closely and rigidly confine the cell to a given length and diameter and, while providing such a sheath, to insulate it from both terminals so as to render unnecessary the use of an insulating over or label to prevent the cell from short circuiting by contact with the side walls of the case. ”

“ Justice JACKSON is of opinion the judgment below should be reversed for the reason that, invention being doubtful, the Court of Appeals relied upon commercial success of the product without adequate findings or evidence as to whether such alleged success was due to the product or to the phenomenal increase in demand due to the war and to the advantages of marketing contracts with mail-order houses. ”