JF Ptak Science Books
[Source: Harpers Weekly, November 4, 1882, pg 704.]
This ad doesn't say so, but the makers of this new electric miracle brush was competing with itself, or at least with products within it own production family. The makers, Pall Mall Electric Association (close to "pell-mell" which would have been a more accurate description of this quack medicine outfit's rush into the field of medical victories), claimed that their product would cure nervous and bilious headache, neuralgia, hair loss, dandruff, scalp diseases, as well as create a glowing head of long hair. There is no description of how electricity plays into this scheme--except that they are adamently saying that it does so through bristles, whereas a competitor stealing their idea for a non-existent cure-all for the head was using an electric brush with wire.
It turns out that the Pall Mall Electric Association also produced something called Dr. Scott's Electric Hairbrush, which may or may not have been the same product as above, and which may or may not have competed with itself for a real clientelle buying not-real medical remedies. "Dr. Scott" also produced an "Electric Flesh Brush", an electric corset, an electropathic belt "for ladies", and (among other things) an "electricpatent" sock.
As with other technological breakthroughs, the use of electricity in the 1880s-onward took advantage of the introduction of a new and probably not-understood technology (as with the electric lamp, phonograph, telephone, etc) in which quack businesses set up their tents in the shadows of the possibilities produced by the aura of the new tech.