BOILER REPAIRS.

Fig. 66.

This cut represents a form of clamp used in holding the plates against each other when being riveted.

Fig. 67.

[Fig. 67] represents a peculiar form of bolt for screwing a patch to a boiler. It is threaded into the boiler plate, the chamfer rests against the patch and the square is for the application of the wrench. After the bolt is well in place, the head can be cut off with a cold chisel.