Pioche daily record. [volume] (Pioche, Nev.) 1872-1876, 1873-12-21
,uorOGRAPHY OF THE INVISIBLE.

The grand moral idea which science
continually seeks to impress upon her
.o,aries is humility OF mind; that inesti-
,n,ble virtue whence spring the noblest
risasures OF the soul. But how rare il is
% find this beautiful quality, even in
us,sons of culture and learningl The
rdrsat doctors looked upon Galileo with
Contempt, confined him in prison as
dangerous man, and subjected him to
tbe most ignominious treatment, simply
because he presented, for their accept
once the light from new idea, which
their dull perceptions were unable to ap-
nreeiate. BE affirmed that the sun did
not really rise or set; that it was the rota-
tion of the earth that brought day and
night alternately upon the earth. But
the doctors, like many in our day. proud
in their own conceit OF knowledge, knew
better. The scriptures tell u.s., they
said, 'of the rising and the setting sun;
therefore it moves; our own eyes assure
Ms of the fact; the diurnal experience Of
mankind confirms the truth. Your doc
triue, Calico, is false and dangerous
II is in this style that some persons,
very knowing in their own esteem. rea-
son upon certain subjects. Take spirit
photography for an example. They
allege that spirits are invisible; that an
invisible thing cannot be photographed;
therefore the so-called spirit photograph
ers are base imposters.
1t is not our purpose to dissent from
the conclusion here assumed; but we
take exception to the premises, which are
not in agreement with the science. Pho
tographs of some objects that are invisi-
bic to the human eye may undoubtedly
be produced. The spectrum of solar
light is an example, portions Of which,
totally invisible to the eye, are brought
ont upon the photographers plate; and
their presence is also demonstrated by
other instruments. -aa .a.-
The mental effect which we term light
is supposed to be produced by the beat
ing Of waves of ether against the retina
Of the eye. These waves enter the eye
with an average velocity of about 1S6, 900
miles in second, the length of the
waves being variable, from the one twen-
ty-seven thousandth part of an inch, to
one seventy-fvs thousandth part of inch.
The retina therefore receives many bill
lions of impressions in second, and it
is supposed that it is the difference in
the number and velocity Of these impress
sions that produces in the mind this SEN
sations of the colors. If the waves which
enter the eye have much greater or a
much less velocity than the limits above
stated, they do not, it is supposed, pro-
dnce the sensation OF light and the OBJ
jects from which such rays come, al
though they may really stand before the
eye, are, as we say, invisible. But al
though they do not affect the eye, they
may impress the Photographic plate,
which has no such constitution as the
eye.
One of the most successful methods Of
producing spirit photographs is to
place, in front Of the sensitive plate,
within the plate shield, clear sheet OF
glass having nothing upon it except u
thin positive of the spirit that is to be
produced on the negative. The portrait
Of the sitter is taken in the usual man.
ner. The light which enters the camera
lens prints the sitter and also the spirit
which is on the thin positive upon the
negative. This is very convenient
method, as it requires no manipulations
likely to be detected; and is, we think
the favorite plan practiced by the best
spirit photographers. Prints made in
this manner pass current among the be-
levers for genuine ghosts Of the de
parted, directly descended from heaven
But a more new, interesting. and scien
tdc method of producing spirit photo
graphs, is as follows: the plain back
ground screen, before which the sitter ii
placed in order to have his portrait taken
is to be painted beforehand with the form
Of the desired spirit, the paint being
composed of some fuorescent substance
such as solution of sulphate of quinine
When this painting dries on the screen
it is invisible to the eye; but it sends on
rays that have power to impress the
photo plate; and thus the image Of th'
person together with the quinine ghos
are simultaneously developed upon tn,
negative. This is a very beautiful ant
remarkable method.-[Scie Ameri
can.