Pyro solution A 20 c. c.
Soda solution B 20 "
Water 20 "

The developer acts about one and a half times slower than the ordinary
pyro soda developer, approaching to the latter pretty nearly, and
gives to the negatives an agreeable color and softness, with clear
shadows. If the negatives are to be thinner, more water, say 30 to 40
c. c., is taken. If denser, then the soda is increased, and the water
in the developer is reduced. An alum bath before fixing is to be
recommended.

An advantage of this development is the great durability of the
pyro-meta sulphite solution. The cost price is about the same as
that of the ordinary pyro developer. At all events, it is worth while
to make further investigation with the metabisulphite of potassium,
the same being also a good preservative for hydroquinone
solutions.--_Photographische Correspondenz; Reported in the Photo.
News._

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