[15] It must be borne in mind that the negative element is that to which the positive pole is attached, and vice versâ (see ss. 8 and 9).


ADDENDUM.
The Gassner Battery.

Since the compilation of the foregoing pages, a dry battery, known by the above name, has found great favour with electric-bell fitters. Its peculiarity consists in the zinc element forming the outside cell. In this is placed the carbon, which is separated from the zinc by a thick paste or jelly made of gypsum and oxide of zinc. The cell can be placed in any position, works as well on its side as upright, is not subject to creeping, has an E.M.F. of about 1·5 volt, with an internal resistance of only 0·25 ohm in the round form, and 0·6 in the flat form. The Gassner dry battery polarizes much less quickly than the ordinary Leclanché. The only defects at present noticeable, are the flimsy connections, and the fact that the outer cases being metal must be carefully guarded from touching one another. This can be effected by enclosing in a partitioned wooden box.


INDEX.

A.

B.

C.

D.

E.

F.

G.

I.

J.

K.

L.

M.

N.

O.

P.

R.

S.

T.

U.

V.

W.

Z.

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Transcriber's Notes

Page 12: changed "guage" to "gauge" ( ... cotton-covered copper wire, say No. 20 gauge ...)

Page 35: changed "change" to "charge" ( ... losing at the same time its electrical charge ...)

Page 55: changed "guage" to "gauge" ( ... 1 foot of No. 41 gauge pure copper wire ...)

Page 64: changed "exaet" to "exact" ( ... of the exact diameter of the turned ends of the cores ...)

Page 73: moved comma "Rivetting, is" to "Rivetting is," (Rivetting, is perhaps, the best mode ...)

Page 81: added hyphen ( ... along the short length of wire to the right-hand binding-screw ...)

Page 83: changed "head" to "heads" ( ... the possible defects of electric bells may be classed under four heads: ...)

Page 92: changed "its" to "it" ( ... until it rests against the stop or studs.)

Page 102: changed "contract-breaker" to "contact-breaker" (When the contact-breaker is used, ...)

Page 103: changed "instead" to "Instead" (Instead of the armature and clapper ...)

Page 132: in the Morse code for "BRING THE", the code for "H" has been corrected from two dots to four dots.

Page 136: changed "eletro-magnet" to "electro-magnet" ( ... if the electro-magnet were energised ...)

Page 137: changed "idicator" to "indicator" (since the indicator falls forwards)

Page 146: changed "arrangment" to "arrangement" (the size and arrangement of the batteries and wires)

Page 146: added comma "nails," ( ... chance contact with nails, staples, metal pipes or other wires ...)

Page 179: changed "carboard" to "cardboard" ( ... for our purpose we will choose cardboard.)

Page 179: changed "Tanstickor" to "Tãndstickor" ( ... double it to the form of a Tãndstickor match-box, ...)

Page 185: suspected typo (unchanged) "Emmot" should perhaps be "Emmott" (... the electrical firms of Messrs. Blakey Emmot, ...)

Page 186: changed "Leclanchè" to "Leclanché" ( ... polarizes much less quickly than the ordinary Leclanché.)

Page 187: changed two instances of "Ampére" to "Ampère" in the index (Ampère, 55 / Ampère's law, 11)