West Virginia argus. [volume] (Kingwood, W. Va.) 1877-1946, 1880-03-06
SCI ENTIFIC.

JdcObS MS DethOd for Photo PriHstng.-
Prepare a. carbon picture in the usual
manner upon a sheet OF glass, and sur
round tire picture with wooden frame
which exactly fits round the sheet of
glas.. Then pour into the frame u
mixture (n"t too hot) one part OF gela-
tine, one part OF gum arabic, and two
parts OF giycerine. When tho mass has
stiiiencd i'm the frame, carefully re-
move the latter iroLc the former with a
knife, and with equal care invert the
gelatine plate, with which the carbon
picture will now be Incorporated. 10
Ink the picture use ground glass roller,
and the mixing process proceeds most
favorably when done upon IA smooth.
elastic support like that used for rolling
letter press forms. The printing ink,
which must be very thick Is previously
dissolved In oil of turpentine or in
bcnZole, and some of the solution,
without the addition of varnish, Is
poured upon the plate and distributed
over IL by the glass roller. The plato
being linked, a sheet of uncoagulated
albumenized paper corresponding I'm
size TO the picture is laid upon it, and
an IndIa-rubber roller passed softly
across the paper, which is then lifted
OIL the plate. The albumeniZed paper,
which absorbs moisture readily, should
not be allowed TO lie too long upon the
plate for fear of the albumen dissolving
of and dirtying the plate. 1t Is not
necessary to damp the plate with water,
rs it possesses sufficient moisture to
allow of dozen impressions being
taken. OF course this moisture Is eX-
hausted at last, but the plate is sufll-
GENTLY microscopic to absorb enough
moisture from the atmosphere i'm the
course of a few hours to allow of print
ing being resumed. While in other
lchtdruck processes the image is sunk
into the plate and the ink has to sink
into the shadows, this method has the
advantage of furnishing IA relief which
facilitates printing. BY this process,
also, round objects, such as bottles and
vases, can be printed-possibly " it'll
colors, which could be burn in.
Endless RdtlS.-The idea of making a
train lay down and take up ITS own
rails "A IL moves along is not a new one,
but an interesting realization of iJ is
now TO be witnessed in the Jardin DIES
TuIleries, Paris. The system is that
OF Clement Ador. The rails on either
side OF the carriages consists of a
series of joined pieces of rail, with Hat
system OF wheels, passing down over
the front and up over the end wheels
and all the wheels have two tlanges to
! prevent any derailment. In front the
Grains OF rail are guided by two distri-
! buting wheels, which are governed
| by the traction, so that on pulling obi
! quely, right or left, the endless way
automatically follows the same direc-
ton. At the end of the first train,
again, are two taking up wheels, pro
Vided with ditferential motion to meet
the difficulty of going in curves, which
| involves an extension of the rail on
one ST &c and contraction of that on
the other, so that whatever the curve
| (to six or seven metres radiu,, the way
is regularly put down and lifted.
From the mechanical point of view one
Is struck with the smallness of the
force required to move train thus ar
ranged. In the Jardin des Tuleries
the train consists of three carriages
! capable of containing in all thirty
children, and often full. These are
drawn by two goats, which work thus
Tor seven hours. The total load is
about LOCO kliogrammes, or rather
more than II ton. To draw like
weight in three carriages on ordinary
roads would require dozen goats
! four for each vehicle. (This is the
number haruc,>ed To the small carriages
for children la the. Champs Elysees )
The economy at carriage, then, is in
contestablc, Tie normal speed is four
miles, Ter hour. The system Is, OF
course, not designed for passenger
| traffic, bat Ter goods, and in many
| places, W!tn bad roads or more, might
| DC very sCrViCcable.