Before nickel can be deposited on a wax mould so as to get a smooth sheet it is necessary to prepare the mould with black-lead or with bronze powder as for the electrotype process, and first deposit on it a thin film of copper in an electrotype solution. If the object desired is a copy of a design impressed on the face of the mould, it will be advisable to remove the mould to the nickel vat when it has become coated with a very thin film of copper, and deposit the nickel on this film. If the design is not undercut, it maybe possible to peel off the film of copper from the nickel; but some difficulty may be experienced in getting a deposit of nickel thick enough to form a plate or sheet, as thick deposits have a tendency to crack, curl up, and peel off. To get a tough coat, the nickel should be deposited slowly with a low-tension current.