Should their resistance drop to any great extent after continued use it can again be raised by treating with an alternating or pulsating current as described under treating and testing cells.
THE END
Transcriber's Notes:
The cover image was created by the transcriber, and is in the public domain.
Antiquated spellings were not corrected.
The illustrations have been moved so that they do not break up paragraphs and so that they are next to the text they illustrate.
Typographical errors have been silently corrected