New-York tribune., 1894-01-07
REMARKABLE DISCOVERY
PHOTOGRAPHY WITHOUT LIGHT OR LENS.

PICTURE TAKEN DY ELECTRICAL ACTION ONLY
-HERTz's EXPERIMENTS RIyALLED.
Clerk Maxwers electromagnetic theory OF light
received striking confirmation seven eight years
ago. when Heinrich Hertz performed number Of
experiments in which electrical waves were made
to initiate the conduct of light waves In severa.
particulars This gifted investigator. now con-
nectcd with the University of Bonn. concentrated
the rays to focus with parabolic mirror. Re-
fraction as well reflection accomplished.
Electricity. proceeding In straight lines. was d.
vered from its course by prism Of pitch. The
phenomena of interference and polarization were
also reproduced 1t is now announced that photo
graph has been taken by using electricity instead
Of light, and II this story IA true. then additional
evidence Will have been afforded as to the klnshp
OF these forces forms OF force. Hertz 1t VIII
be observed. only showed that the electrical ra-
dance conformed to mechanical laws which are
known to control life. but photography introduces
the element OF chemical action, so that this later
achievement, IL II proves to be all that it seems
is one OF the most remarkable revelations OF our
day.
Professor Fernando Sanford. who claims TO have
attained this wonderful result. and who gives some
account of II to THE San Francisco Examiner
occupies the chair of physics In Leland Staniopr 6a
jr. University and !s one Of the youngest members
appears over his own signature and he intimates
that he has repeated the experiment several times
ness Of the the occurrence described Professor San
ford obtained his picture in the dark without even
1t is well known that when two brass rods con n
nected with the sides Of the battery: or placed rn IN
brought close enough together spark VIII nv froW
one to the other II to eaen roo snort
wire be attached and the two wires be LED or 70
suitable metal plates placed facing each otneT & out out
cur between the plates whenever there Is dis,
c,ih tod object
for one Of the plates Of such p pa a ana ybah ah IN
are @ on Se sens m
glass Photographic plate Tintoil was arranged on
the the other other met metal plate Of the pair This combna
ton placed between two boards and left
in the dark FOR an hour during which time series ,ae
OF the dscharger across an interval OF onesxteentn
Professor t SANFORD had an image OF his con;hat is
OF the portions in relief on that side which was IN
copy OF the picture. a positive. which shows the
Liberty head date, inscription "E Pluribus tnum
circle OF stars and raised edge In white on dark
Professor Sanford does not enter into a discussion
Of the theories involved. but he mentions that the
tinfol was not only OF the same size as the coin
IN silver dollar but placed directly opposite Ap-
parcntly electromagnetic waves flowed from the
coin the tnfoi but preferring the shortest route
radiated mainly exclusively from the raised part
straisnt Iimcs too ctherwise the Chemical action on
regions directly opposite the pattern Right here
1t should be noted that Hertz discovered in hts
experiments that the induced magnetic radiance
excited in the manner described. and now called
"Hcrtzan waves in honor Of that now famous
physicist. had this remarkable trait. not possessed
by primary electrical current: Good conductors;
like copper or other metals being intcrposcd; would
stop them: but they would go right through wood
and other so-callcd 'nsulators." Hence. In Pro-
fessor Sanford's experiment: the mica and glass
were evidently barriers to the passage Of the
particular kind OF electricity produced
Although II does not at first appear Cearly what
practical appcat OF this discovery be made.
il IL improbable that VIII be found for IT,
the indirect consequences are sure 10 be valuable
as well as interesting.