We now come to the paper process, and most effective enlargements can be made by it also; indeed, as a basis for coloring, nothing could well be better. Artists all over the country have told me that after a few trials they prefer it to anything else, while excellent and effective plain enlargements are easily made by it if only carefully handled. A very good enlargement is made by vignetting the picture, as I have just done, with the opal, and then squeezing it down on a clean glass, and afterward framing it with another glass in front, when it will have the appearance almost equal to an opal. To make sure of the picture adhering to the glass, however, and at the same time to give greater brilliancy, it is better to flow the glass with a 10 or 15 grain solution of clear gelatine before squeezing it down.

License information: nan
MPAA: G
Go to source: http://www.gutenberg.org/files/11344/11344-h/11344-h.htm#10