ed just back of the lamp.

Procure a plano-convex or a bi-convex 6-in. lens with a focal
length of from 15 to 20 in. and a projecting lens 2 in. in
diameter with such a focal length that will give a picture of the
required size, or a lens of 12-in. focus enlarging a 3-in. slide
to about 6 ft. at a distance of 24 ft.

The woodwork of the lantern should be of 1/2-in., well seasoned
pine, white wood or walnut and the parts fastened together with
wood screws, wire brads, or glue, as desired. The board in which
to mount the condensing lens is 16 in. wide and 15 in. high,
battened on both ends to keep the wood from warping. The board is
centered both ways, and, at a point 1 in. above the center,
describe a 9-in. circle with a compass and saw the wood out with a
scroll or keyhole saw. If a small saw is used, and the work
carefully done, the circular piece removed will serve to make the
smaller portion of the ring for holding the condensing lens. This
ring is made up from two rings, A and B, Fig. 3. The inside and
outside diameters of the ring B are 3/8 in. greater than the
corresponding diameters of ring A, so when fastened together
concentrically an inner rabbet is formed for the reception of the
lens and an outer rabbet to fit against the board C in and against
which it rotates being held in place by buttons, DD.

A table, E, about 2 ft. long is fastened to the board C with
brackets F and supported at the outer end with a standard. The
slide support, G, and the lens slide, H, are constructed to slip
easily on the table, E, the strips II serving as guides. Small
strips of tin, JJ, are bent as shown and fastened at the top and
bottom of the rectangular opening cut in the support G for holding
the lantern slides.

All the parts should be joined together snugly and the movable
parts made to slide freely and when all is complete and well
sandpapered, apply two coats of shellac varnish. Place the lamp
house on the bottom board behind the condensing lens and the
lantern is ready for use.

The proper light and focus may be obtained by slipping the movable
parts on the board E, and when the right position is found for
each, all lantern slides will produce a clear picture on the
screen, if the position of the lantern and screen is not changed.
--Contributed by Stuart Mason Kerr, St. Paul, Minn.

** A Quickly Made Lamp [329]

A very simple lamp can be made from materials which are available
in practically every household