** Use Chalk on Files [19]

If a little chalk is rubbed on a file before filing steel, it will
keep the chips from sticking in the cuts on the file and
scratching the work.



** A Homemade Steam Turbine [20]
By WILLIAM H. WARNECKE

Procure some brass, about 3/16 in. thick and 4 in. square; 53
steel pens, not over 1/4 in. in width at the shank; two enameled,
or tin, saucers or pans, having a diameter on the inside part of
about 4-1/2 in.; two stopcocks with 1/8 in. holes; one shaft; some
pieces of

[Illustration: Details of Turbine]

brass, 1/4 in. thick, and several 1/8-in. machine screws.

Lay out two circles on the 3/16-in. brass, one having a diameter
of 3-1/2 in. and the other with a diameter of 2-3/4 in. The
outside circle is the size of the finished brass wheel, while the
inside circle indicates the depth to which the slots are to be
cut. Mark the point where a hole is to be drilled for the shaft,
also locate the drill holes, as shown at A, Fig. 1. After the
shaft hole and the holes A are drilled in the disk, it can be used
as template for drilling the side plates C.