Time for complete development should always be allowed; with a hot
bath fifteen seconds will be sufficient, but if a cooler development
is used, or the prints are solarized in the shadows, more time should
be allowed. When the deep shadows are solarized, or appear lighter
than surrounding parts, a hot and prolonged development is required to
obtain sufficient blackness, as they have a tendency to look like
brown paper. I have found breathing on solarized shadows useful, as in
the presence of slight moisture they begin to print out and become
dark before development, getting black almost directly the print is
floated on the oxalate. Three or four acid baths of about ten minutes
each are used, and the prints are washed as before. The process
throughout takes much less time than silver printing, and can be kept
on all the winter, when it is nearly impossible to print in silver.
Prints can be developed in weak daylight or gaslight, and prolonged
washing is dispensed with.--_N.P. Fox, reported in Br. Jour. of
Photo._
* * * * *
[Continued from Supplement, No. 706, page 11283.]
ON ALLOTROPIC FORMS OF SILVER.
By M. CAREY LEA.
In the first part of this paper were described certain forms of
silver; among them a lilac blue substance, very soluble in water, with
a deep red color.
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