NOTES AND QUERIES. 27 
following instructions for producing transparencies from his dry 
plates. We have used these plates, and have much pleasure in 
reporting them easy to work and yielding excellent toned pictures :— 
They are combinations of Gelatine with Albumen, having a film of 
most exquisite fineness, capable of giving a variety of tints, from a 
dense black to the much admired tone of the Continental Lantern 
and Stereoscopic Transparencies. 
For making Lantern Slides, supposing the negative is of a suit- 
able size for the purpose, artificial light is the most convenient to 
work by, and the simplest method is transparencies by contact. 
To produce these, put the negative in a printing frame and (in a 
room having none but a zon-actinic light) place a prepared plate in 
contact with it, then expose the negative to an ordinary gas flame 
at say 3 feet distance for 30 seconds, after which return to the dark 
room and place the exposed plate in a forcelaim tray, containing 
Chapman’s FERROUS OXALATE DEVELOPER, and in a few seconds 
the image should appear. When all detail is out do not consider 
it to be fully developed, but turn the plate up from the solution 
and look at the dack part of it ; if the mere outline of the subject is 
only visible, lay the plate down again, and give it a minute or two 
more soaking; if on looking again at the back the de¢az/ is pretty 
well defined, the plate may be considered fully developed and will 
be ready to be taken from the developer, drained and RINSED in 
water, and then placed into another porcelain or glass tray, con- 
taining the Fixing Solution, as follows :—Sodium Hyposulphite, 4 
ounces ; Water, 20 ounces. Let thé plate remain in this solution 
for, say five minutes, or until quite free from opalescence, then 
drain, and, without rinsing, transfer it direct into another tray con- 
taining the following solution :—Alum, 1 ounce ; Water, 20 ounces. 
After being in this solution for five or fez minutes it may be put to 
soak, to thoroughly rid it of Hyposulphite and other salts, and the 
best way to do this is to put it into a conical or taper vessel—say 
a basin or deep saucer—of water, face downwards, and change the 
water occasionally. After a few hours, or a whole night’s soaking 
in this manner it may be considered ready for the final wash before 
drying, and to obtain the most brilliant pictures it is well to give this 
in arunning stream, and whilst the water is flowing over the plate 
to go over the f/m with a sof camel’s hair brush, a tuft of cotton 
wool, or the soft inner surface of the fingers. Afterwards, let the 
plate be placed in a rack to dry, and this should be in a moderately 
warm room, and the precaution taken not to disturb the plate whilst 
drying, or possibly surface markings will be produced. When quite 
dry it is ready for varnishing. 
The above simple directions are more for those who have had 
no experience in producing Transparencies. Those acquainted 
with the method of producing either enlarged or diminished pic- 
