. Annual report of the Board of Regents of the Smithsonian Institution . ce. An important item inthe reproducing appa-ratus is the needle. In-stead of the same bluntpoint being used overand over again as form-erly, a new needle is nowrecommended for eachplaying of a record. Thereason is that the opera-tion of plajang a recordwears down the fine pointof a needle, so that by thetime a record has beenplayed through, theneedle point has shoul- « . , ^- l^i , ^ Some vanous stages of development of the ders worn on it (fig. 11) gramophone. with only a central projection left to engage in the sound g
. Annual report of the Board of Regents of the Smithsonian Institution . ce. An important item inthe reproducing appa-ratus is the needle. In-stead of the same bluntpoint being used overand over again as form-erly, a new needle is nowrecommended for eachplaying of a record. Thereason is that the opera-tion of plajang a recordwears down the fine pointof a needle, so that by thetime a record has beenplayed through, theneedle point has shoul- « . , ^- l^i , ^ Some vanous stages of development of the ders worn on it (fig. 11) gramophone. with only a central projection left to engage in the sound groove;a point of this shape when much worn can not give a good reproduc-tion. The manufacture of gramophone needles constitutes a smallindustry in itself, and the number of processes through which theneedles go before they are ready for use is surprising. Lengths arecut from the best steel wire, and are pointed by emery wheels, rotatingabout 1,200 times a minute. The needles are cut off, and again theblunt ends are pointed. Some of the machines in use cut off as many. 220 ANNUAL REPOET SMITHSONIAN INSTITUTION, 1908.
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