Page:Model engine construction, with practical instructions to artificers and amateurs (IA modelengineconst00alex).pdf/84

64 MODEL ENGINE CONSTRUCTION. made as follows. Take two small brass blocks, drill each of them only half-way, or nearly so, to their centre, leaving the hole large enough to admit the glass tube. Now drill two smaller holes in the blocks at right angles to the previous ones, and instead of inserting a cock in each, put in, by screwing or soldering, a bit of brass tubing about 3/4"long, the bore of which communicates with the boiler and the glass tube, through the hole in the block previously drilled at right angles to it. Each block is firmly soldered to a small brass plate A, each tube passing through a hole in the plate. The

Fig. 17.