The sun. [volume] (New York [N.Y.]) 1833-1916, 1900-06-09
THE WONDERS OF ELECTRICITY.
The Great Experimental Plant OF the Se"e'
son Physicsi LAbratory.

$50 Sreet ExpertmenSsA
son Physical LAbrasory'
Prof. John Trowbridge, director OF the oei-
ferson Physical Laboratory OF harVaru U
versity, writes TO the electrical er'eVasio"oNe
The college professor finds himself to-day
In view Of the remarkable practical oe'e,op-
ment OF electricity. at a certain oisao'@',as'
compared with the electrical engineer. Inc
latter has at his command telegraph and tele-
phone lines OF great extent: he can experiment
on cables, for instance, under conditions when
cannot be produced in any laboratory; he can
employ currents Of enormous strength IN prac-
tical Investigations In heat and In metallurgy
The college instructor is limited In resources
In the large field Of the display OF great cleo
trical energy. There Is. however, one dlrec-
ton in which he can enter into competition
with the practical man on equal terms. and this
field Ia that of high electro-motive force. !
have, therefore,. entered this field with the de-
sire OF using TO the Utmost the facilities which
the practical Developments OF electrical phe-
nomena have afforded the Investigator. For
the past two years I have experimental with
a storage battery Of 10, 900 cells. and the plant
has proved 30 practical that l have lately
doubled II. and l now have ? 1900 cells In sue
cessful operation. This plant Is the largest In
the world at the service Of the investigator In
electricity and It has opened a highly interest,"
ing field in the study OF high electro-motive
force. At the voltage Of 1000 900, sparks can
be produced ~ feet long. which exhibit all
the chief peculiarities Of lightning. By means
Of suitable condensers I can obtain 100000
volts; but I have discovered that voltage Of this
extent can not be studied In a laboratory or
In any confined space. 1t Ia necessary to
place the apparatus In an open field and at
least 20 feet from the ground, for the induc-
tive action to all surrounding objects at such
high voltages is enormous and the air becomes
afairly good conductor.
Zone OF the most interesting manifestation
Of this large battery is the production Of the
X-rays. The photographs taken by means
Of It show unusual contrasts and exhibit traces
of the ligaments and muscles. see no rea-
son why, under proper manipulation. one
cannot obtain satisfactory photographs Of the
tendons and muscles. for the battery current
and voltage can be regulated 70 any desired
degree.
The quantity discharge Of the battery is
also of great scientific interest ! am en-
ploying a condenser consisting Of 800 plates
Of glass with a coated surface Of sixteen to
twenty lnciies' lns nus d cupdclty Vi uoout
is microfarads. The discharge from this
condenser charged to over 10000 volts pro-
duoes the highest instantaneous temperature
which has been obtained and photographs
of the spectrum Of hydrogen can be obtained
with one discharge. This battery opens an
interesting field Of inquiry in regard to the spec
ira Of the vapor Of the metals and also prom
ises to solve certain electrical engineering prob
lens, notably the change of magnetic per-
meability at periods ranging from 700 a second
to over 1000 600. under currents Of varying
strength"