Dissolve in water, filter the solution, and boil it immediately along with flowers of sulphur.

The filtered concentrated saline liquid will afford, on cooling, a large quantity of pure and beautiful crystals of hyposulphite of soda." Hyposulphite of Gold .-- This compound salt is by a few considered preferable to the chloride of gold, but our experience has induced us to use the latter, believing we are enabled to produce a more brilliant and warm-toned impression with it.

When the hyposulphite of gold is used in gilding, it requires less heat and a longer application, as there is some danger of producing a glossy scum over some parts of the surface of the plate.

I prepare this salt as follows: Dissolve one part chloride of gold and four parts hyposulphite of soda in equal quantities of distilled water: pour the gold into the hyposulphite solution, in the same manner as in mixing the gilding solution; let it stand until it becomes limpid; filter and evaporate to dryness.

Re-dissolve and add a few grains of burnt alum.
After standing a few hours, filter and evaporate again.