Practical radiography : a handbook for physicians, surgeons, and other users of X-rays (1901)
Isenthal, A. W, Ward, H. Snowden (Henry Snowden), 1865-1911 · London : Published for The Photogram, Ltd. by Dawbarn and Ward, Ltd. · leaf 63
te, closed at both ends. The secondary consists generally of a large number(40,000 to 150,000) of turns of very fine silk-coveredcopper wire, wound upon the primary tube. In winding the secondary circuit it will be found thatthough there is very little potential difference betweencontiguous turns,… … Fig. 15. degree that the spark would pass internally and of coursewould ruin the coil. Such simple winding is thereforeonly applicable to very small coils below one-inch sparklength. For larger coils, the sectional system introducedby Messrs. Siemens and Halske, of Berlin, should alwaysbe adopted.…
Radiography · X-rays
Internet Archive · Medical Heritage Library · Public Domain Mark 1.0. Free to use for anything.
![An illustration from [Graphophone patents] (1878)](https://img.insideoutlibrary.com/img/200/ia-graphophonepaten07unit-219-164.webp)