St. Tammany farmer. [volume] (Covington, La.) 1874-current, 1892-07-02

-Electricity. In its vaxious 1osns q
application Is said 70 give 'employDent
to 6ve million persona stf -
Electric street railways In various
parts -0f the United States, - weN -
Canada, have been equipped wholly OF
in part with electric heaters, and
very great sstiafection il found In their
use.
-Although the ordinary systems Of
duplex telesraphy are generally said 70
double the capacity Of liue. it h now
quite clearly andezst0Dd that mp 70 The
present they have been incapable Of Do
ing It -'tf
"A line Of telephone, the first that
unites two Italian cities, has been
opened 1t Milan. establishing telepAonie
communication between that city and
Pavia. 1t is more than thirty miles long
and acts perfectly.
Edison has patented an alternating
current generator the feature Of which
is the fact that the field magnet has sev.
eral polcs and consists Of overlapping
magnetic plates bolted together % that
the plates shall be In contact 1t the
ends but shall be separated for . por-
ton Of their length. Repairs TO the
magnets arc thus easily made.
1T is said that . fine metallic wire
stretched between two supports and
traversed by IN electric current will be-
gin to vibrate with increasing ampli-
tude until MAXIMUM is reached which
is maintained as long Is the current re-
mains constant and the surrounding
air undisturbcd; when the wire Is in
closed in tube the vibrs) s)ki0ns are moro
regular. The vibrations vary with the
current, the size Of the wire and it,
tension, and cease in . few seoonds II
the current is broken. The discOverer
of the phenomenon attributes It to the
heating of the wire. .<.l..4 j.
Edison has recently been engaged
IN the development of electric motors
for railroads. He believes that the
locomotive will be displaced ON steam
railways; and ssates thst great economy
would result from tho us. Of its motors.
'"Threc of them" he affirmed recently,
with q horse power Of 10000 or Il, 900
each, would run the whole Peansylva-
mia railroad system between New York
and Philadelphia." Full details Of his
system arc mot announced; but the cur
rent passes from the Stationary engine
to . central rail bstweei the tracks.
thence through the mechanism attached
to the bottom 81 the motor. re-
"A very inaeaius automatic machine.
1t il said. is that which hss been estsb-
lishcd near the letter box at Charing
Cross station. London. for the collection
of letters 70 be forwarded BY the post
Office express service. II il In electrical
connection with the postal telegraph
oflee opposite the station. BY dropping
. penny into the slot and palling ont
the slide, q brown colore1 envelope =
delivered This envelope contains an
other envelope and . card The com
munication Is intended 10 Be written On
the card, which 10 then inclosed in the
white envelope, and this, With the fses
for delivery, which have been Axod a&
three pence per mile, is reincloaed in The
outer envelope and deposited In the box
behind the nap. which bears the printed
instructions. The oct of ,withdrawin8
the slide sends the call signal TO the
telegraph Office, and . ,ntssenger is at
once dispatched 10 collect the special
IGtVCxOs Af