The true northerner. [volume] (Paw Paw, Mich.) 1855-1920, 1882-04-07
TIE WORKSHOP.

To MAKE waterproof canvas for cover
ing carts etc.: Nine and half gallons
linseed oil, one pound litharge, ono
pound umber, boiled together for twenty
four hours. May be colored with any
paint. Lay on with brush.
VERY fine effects are produced on
unfinished cast iron by mixture Of
petroleum with French yellow, the re-
suit being fine bronze yellow, not
liable to ordinary wear, and, if applied
hot, filing the pores of the metal, defy
ing anything short of the file or planer
to Obliterate it.
In REMNANTS process for rendering
cloth waterproof the fabric is passed
slowly by machinery through tank
divided into three compartments, the
first containing warm solution of alum,
the second warm solution of lead
acetate and the third pure water, which
is constantly renewed.
A BAvARIAN patent has been recently
issued for the manufacture of glue from
bones. The bones are crushed to fine
particles and treated to the glue-steam-
ing apparatus, after having been
sprinkled with oxalic acid. After a
time the steam is replaced by boiling
water and the glue expelled by air pres
sure.
DIFFERENT makers differ in their
rules for dimensions of boilers. The
following estimates however, are safe
For each nominal horse power boiler
should have one cubic foot per hour,
one square foot of heating surface, one
square foot of fire CRATE surface, one
cubic yard capacity, twenty-eight square
inches hue area, eighteen inches over
bridge.
A CUBIC foot of air weighs 538.
grains, or something over one ounce !;
1906 cubic feet weigh one pound.
About sixty-five cubic feet of air furnish
one pound of oxygen. An apartment
eight feet high, twelve feet wide and
thirteen feet long contains about 100
pounds of air; and a room forty feet
square and eighteen feet high contains
about ton.
To PREVENT the cracking of csat steel
in hardening, says correspondent OF
the Metay- Arbeiter, place the article be-
fore hardening it, in tin box, pack it
with clean wrought-iron drillings, and,
luting the box carefully, heat the whole
slowly to dark red. After cooling it
gradually he finds that all internal strains,
which would otherwise have developed
cracks in the tool during hardening, are
removed. He does not say, however,
what effect the process has on the dura-
bility of the steel.
AN ONO man has invented cheap,
f,,fa
farm machines run by horse power.
The mould for the ball or central part
is first made with four chills, to form the
holes in the ball A sand core is inserted
to make it hollow, serve as an oil reser-
voir and make the joints self-lubricating.
After the ball is cast the holes are washed
with black lead, and placed III mould
containing the impressions of the two
forks. The iron is poured and the Joint
is thus made complete, by two simple
operations, which are inexpensive.
LIGHT pulleys are better than heavy
ones, as they make less friction and
necessitate lighter or less frequent hang
ers, besides being cheaper. Pulleys
should be given perfect running balance;
screws throw pulleys out of center !;
keys tend to split the hubs. Both set
screws and keys deface the shafting and
render it best for bearing surface should
it be desired to place hanger where q
pulley has been. Compression coup
lings are best, and those kind are prefer
able in which there is split across the
gripping sleeve, so that the coupling
will accommodate itself to shafts Of
slightly differing actual diameters, al
fhonnh having canal nominal diane tars