Saw two spools in half and fasten the
halves to the four corners of the board at the back, and the
apparatus may be put up where one likes.
**v To Build a Small Brass Furnace [115]
Bend a piece of stout sheet iron 23 in. by 12 in. round so that
the inside
[Illustration: Furnace]
diameter is 7 in., and then rivet the seam. Fit in a round piece
of sheet iron for the bottom. Make a hole about the size of a
shilling in the side, 2 in. from the bottom. This is for blowing.
Line the furnace, bottom and sides with fire-clay to a depth of
1/2 in. Use charcoal to burn and an ordinary bellows for blowing,
says the Model Engineer, London. The best blast is obtained by
holding the nozzle of the bellows about an inch from the hole,
instead of close to it.
** Avoid Paper Lamp Shades [115]
Don't wrap paper around a lamp for a shade. You might go away and
forget it and a fire might be started from the heat. Use a glass
or metal shade. That is what they are for.
** Why Gravity Batteries Fail to Work [115]
Many amateur electricians and some professionals have had
considerable trouble with gravity batteries.
Pages:
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285