the center is reached, using a hammer as shown in Fig. 100. The operation is continued until the piece is raised as much as desired. The edge will be more or less uneven when finished and must be
Fig. 101. Raised Forms
trued with a file or emery wheel. The work should also be tried on a surface plate to see that it is level.
At A, Fig. 101, is shown a form that was raised on the iron block, and at B is shown another which has six ribs, radiating from the center, which were made with the sinking-tool. These hemispherical forms may also be enriched by bumping up their surface with relief ornaments. These pieces are to be used as ceiling canopies to cover the electric wiring for hall lanterns. At C is shown a shovel bowl which has been raised on the wooden block. The pattern is shown in Fig. 102. The stock used is No. 16 soft steel.
Metal is sometimes raised by bumping it into an iron form. If a series of bumps of the same size and shape are needed it may be well to ham-