| 摘要 |
420,410. Golf bails. BURBANK, W. C., 155, East 73rd Street, New York, U.S.A. Jan. 5, 1934, No. 494. Convention date, Sept. 27, 1933. [Class 132 (ii)] The surface of a golf ball is provided with " spiral '' grooves or with raised portions terminating at various distances from the poles of the ball, the object being to lessen the atmospheric resistance of the ball. The grooves may be curved throughout in the same sense, or may be curved in two senses or, as shown in Fig. 3 in three senses. |
