A
SUGGESTED
METHOD
OF
COPYING
SPHYGMOGRAMS.
W. Macphun
Semple, M.B.,
Some little time ago it occurred
to
me
that
Glasg. by taking
transparent butter paper
mograph tracings able to use the resulting tracing on
C.M.
as
an
ordinary
I
should
photoplate'
^
ON
A
thereby
be able
tracing
METHOD
SUGGESTED
to
might original tracing as as
make be a
as
OF
COPYING
SPHYGMOGRAMS.
many accurate
of any
also be able
and
required
copies
313
to
given
use
the
lantern slide.
adopt is transparent tracing paper is The method I
very simple. A piece of ordinary into strips to suit the particular
cut
lnstrument used, and then smoked over a piece of camphor in the ordinary way. By placing a bottle filler inverted over the air space at the bottom, a compact column obtained, and so a much more evenly smoked paper produced, with much less camphor, than by burning in the and
camphor
?f smoke is ls
leaving
Usual way in a teacup When the paper is
or saucer.
properly
smoked the
tracing
of the
pulse
ls
made at once and varnished. The varnish I use is benzoline and gum dammar, which answers admirably. When the varnish *s
ls
dry, by holding
the
tracing
to the
light,
it will be
seen
that it
quite transparent, with a dark ground, and thus is obtained What is practically a photographic plate, ready for printing,
^he
next step is to get a small printing-frame, and place a piece clear glass in it. The tracing is then put on the glass, and ?n that is placed a piece of ordinary sensitised silver paper, or, ?f
better still,
a piece of ferro-prussiate paper such as engineers having fixed up the back, the printing-frame is exposed !?r about a quarter of an hour in the sunlight. The last stage ls to take the piece of ferro-prussiate paper and wash it well 111 several changes of cold water, when the tracing will be seen come out, in dark blue on a white ground. As many of what 111 ay call of the photoscripts" tracing may be taken as and so the could be made use of for classes required, process ^ or for exchange with other doctors in connection
Use>
and
"
^dents, Sphygmograph Club," 1 a
f
^
is better than the
for any of the many purposes I consider the " photo-
original, as it gives the tracing in white ground, and so the curves and differences seen to greater advantage than when in white on a black as *n the original. There is no technical skill whatever and the only thing I should wish specially to be noted t^le PaPor must be more thickly smoked than usual, and srnoking, the paper must be kept sufficiently far away from colour
js^Ulre^> "Mi
or
which tracings may be required.
Pt
^
"
on a
PROGRESS
314
the flame of the The
MEDICAL
SCIENCES.
from
making
so
a
prevent the needle defined track
well
-
it.
copies
can
be
more
would be
ten
by gaslight; only in used, which gives a blackish
quickly
bromide paper must be tracing on a white ground.
case
brown
THE
harden in the smoke and
sphygmograph
through that
not to
OF
seconds for each copy.
made
The exposure in that case
SUGGESTED
METHOD
OF
COPYING
SPHYGMOGRAMS.
W. Macphun
Semple, M.B.,
Some little time ago it occurred
to
me
that
Glasg. by taking
transparent butter paper
mograph tracings able to use the resulting tracing on
C.M.
as
an
ordinary
I
should
photoplate'
^
ON
A
thereby
be able
tracing
METHOD
SUGGESTED
to
might original tracing as as
make be a
as
OF
COPYING
SPHYGMOGRAMS.
many accurate
of any
also be able
and
required
copies
313
to
given
use
the
lantern slide.
adopt is transparent tracing paper is The method I
very simple. A piece of ordinary into strips to suit the particular
cut
lnstrument used, and then smoked over a piece of camphor in the ordinary way. By placing a bottle filler inverted over the air space at the bottom, a compact column obtained, and so a much more evenly smoked paper produced, with much less camphor, than by burning in the and
camphor
?f smoke is ls
leaving
Usual way in a teacup When the paper is
or saucer.
properly
smoked the
tracing
of the
pulse
ls
made at once and varnished. The varnish I use is benzoline and gum dammar, which answers admirably. When the varnish *s
ls
dry, by holding
the
tracing
to the
light,
it will be
seen
that it
quite transparent, with a dark ground, and thus is obtained What is practically a photographic plate, ready for printing,
^he
next step is to get a small printing-frame, and place a piece clear glass in it. The tracing is then put on the glass, and ?n that is placed a piece of ordinary sensitised silver paper, or, ?f
better still,
a piece of ferro-prussiate paper such as engineers having fixed up the back, the printing-frame is exposed !?r about a quarter of an hour in the sunlight. The last stage ls to take the piece of ferro-prussiate paper and wash it well 111 several changes of cold water, when the tracing will be seen come out, in dark blue on a white ground. As many of what 111 ay call of the photoscripts" tracing may be taken as and so the could be made use of for classes required, process ^ or for exchange with other doctors in connection
Use>
and
"
^dents, Sphygmograph Club," 1 a
f
^
is better than the
for any of the many purposes I consider the " photo-
original, as it gives the tracing in white ground, and so the curves and differences seen to greater advantage than when in white on a black as *n the original. There is no technical skill whatever and the only thing I should wish specially to be noted t^le PaPor must be more thickly smoked than usual, and srnoking, the paper must be kept sufficiently far away from colour
js^Ulre^> "Mi
or
which tracings may be required.
Pt
^
"
on a
PROGRESS
314
the flame of the The
MEDICAL
SCIENCES.
from
making
so
a
prevent the needle defined track
well
-
it.
copies
can
be
more
would be
ten
by gaslight; only in used, which gives a blackish
quickly
bromide paper must be tracing on a white ground.
case
brown
THE
harden in the smoke and
sphygmograph
through that
not to
OF
seconds for each copy.
made
The exposure in that case
