It is composed of one part of well washed chloride of silver, five parts of cream of tartar, and four parts of table salt.
This powder must be kept in a dark vessel, and in a dry place.

For a plate six inches by five, as much of this composition as can be taken up on a shilling is sufficient.

It is to be laid in the centre of the copper, and the figures being wetted, to be quickly rubbed over every part of the plate, adding occasionally a little damp salt.

The copper being covered with the silvering is to be speedily well washed in water, in which a little soda is dissolved, and as soon as the surface is of a fine silvery whiteness, it is to be dried with a very clean warm cloth.

In this state the plates may be kept for use.