File:Induction coils - how to make, use, and repair them including Ruhmkorff, Tesla, and medical coils, Roentgen radiography, wireless telegraphy, and practical information on primary and secondary battery (14755407584).jpg

Identifier: inductioncoilsho00schn (find matches)
Title: Induction coils : how to make, use, and repair them including Ruhmkorff, Tesla, and medical coils, Roentgen radiography, wireless telegraphy, and practical information on primary and secondary battery
Year: 1901 (1900s)
Authors: Schneider, Norman H. (Norman Hugh)
Subjects: Induction coils Radiography X-rays Radiography
Publisher: New York : Spon & Chamberlain London : E. & F.N. Spon
Contributing Library: Francis A. Countway Library of Medicine
Digitizing Sponsor: Open Knowledge Commons and Harvard Medical School

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
ed to one pole ofthe coil. From the outside tinfoil coating Condensers. Ill T a wire runs to the discharger D Dy whichis in circuit with the secondary coil, 5.The discharger balls D D are carefully ap-proximated until the spark just passes, thislatter point being of great importance.Were the discharger balls too near thespark would probably pierce the dielectricof the condenser, therefore the balls shouldbe carefully brought near to each otheruntil the exact distance is found. Even ifthe insulation of the condenser were notpierced, yet a path would probably beopened through which some succeedingdischarge would pass, and ruin the instru-ment. Another method of charging is to leavean air gap at B; then there is not muchliability of the condenser discharging backthrough the coil—an undesirable event, asit would most likely perforate the insula-tion of the coil. In designing or using any apparatus in-tended to hold a charge of high potential, itmust be kept in mind how readily points or
Text Appearing After Image:
Fig. 33. Condensers. 113 sharp edges serve to allow the current topass off—we*might almost say evaporate.Given two bodies, one a globe and theother a rectangular block, each well insu-lated from the earth or any other largebody, and the globe would be found tohold its charge long after the block haddissipated all trace of the charge given toit. Therefore round off every edge andangle, projection or point. In making handles, supports, or anywork requiring an intervening high insu-lation, hard rubber is preferable to glasswhere there is liability to moisture. Whenthe apparatus is as shown in Fig. 2iZ^ thecondenser is alternately charged and dis-charged with a loud noise, the vivid sparkspassing across the discharger balls D Dpossessing great deflagratory powers. In experimenting with a Ruhmkorff coilit is not advisable to leave the instrumentworking while the secondary terminals arebeyond sparking distance, as there is agreat strain on the secondary insulation. 114 Condensers. Nor is

Note About Images