A Practical Guide for the Use of the Edison Phonograph (1892) - edizione con copertina flessibile

Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: THE CYLINDER. 'T'HE standard wax Cylinder used upon the various 1 types of machines now manufactured (Fig. 32 in illustration) is four and three-sixteenths inches in length, and six and seven-eighths inches in circumference. It is made with a taper, and in placing it upon the mandrel, preparatory to using, the beveled end is slid upon it and the cylinder gently pushed along the mandrel as far as it will go until it fits closely to the taper of the brass man drel, and is then held in position. To prevent slipping, the inner surface of the Cylinder has a series of spiral ribs, or raised strips, upon it, and these tend to prevent its moving when placed in position. Extreme heat or cold will slightly expand or contract the wax of which the Cylinder is composed, but, except in the cases of automatic machines, where the Cylinder is adjusted upon the mandrel and then left for hours without readjustment, the effect of such expansion or contraction presents no practical difficulty in actual operation. In the latter case, however, a sudden change of temperature, causing a contraction or expansion, throwsthe record out of adjustment, and while the first portion of a musical record is reproduced with great loudness and distinctness, the latter portion becomes dim and faint, and does not "play loudly." It is understood that a method will soon be adopted in the manufacture of the diaphragm which will entirely obviate this difficulty. Never leave the Cylinder on the mandrel over night, or for a longer period. The wax of which the Cylinder is made is about one- quarter of an inch in thickness, and the surfaces can be planed off by the knife attached to the diaphragm-arm as many as forty to fifty times, and the Cylinder used over again for recording an equal number of times. This makes...