Evening star. [volume] (Washington, D.C.) 1854-1972, 1926-12-19
Continued from Third Page.)

initiate marble in many colors. This
process consists of a solution of gum
gathered in the tropics, dissolved to
the proper consistency and poured
in a shallow box or trough in which
colors are sprinkled which have been
ground in water and mixed with beef
gall. Any design made of a combina-
ton of colOrs may he worked out by
the bookbinder or marbler.
In the process of lettering or embel-
fishing the hacks of leather-bound
books with gold leaf, very thin sheets
of 2212 karat gold are used. This gold
is laid on the backs or sides OF the
books and impressed with slightly
heated lines of brass type or hand tools
of various designs. BY the Use of
beautifully engraved tools and small
fillet rolls most elaborate designs are
worked out in gold leaf on rare and
valuable book covers.
The oldest of our industrial plants
Is the gun factory at the Washington
Navy Yard, which has been in exist
ence about 125 years and which rep
resents an approximate valuation of
$4,000 900 There we find an average
of 8 1000 employees. two-thirds of whom
are skilled laborers or artisans. rep
resenting some so trades. Here all Of
the ordnance work of the Navy is
done. mostly guns and mounts,
There is also a big plant for the
manufacture of optical inStrume
a trade school to train young men as
machinists and for the other trades
boilermakers. craftsmen and pattern
makers. There is also a model tank
which is one of the oldest In the
world, in which models for ships are
tested. There is also unique wind
tunnel for testing airships and air.
planes and an important radio lab
oratory.
Much ofthe work done in this pla Mt
Is especially delicate and intricate
calling for the highest skill of crafts
men or artisans. This is especially
true regarding optical and fire-control
instruments.
The machinists-and this Is appli
cable also to other trades-must serve
a four-year apprenticeship and then
serve three or four years more as
journeymen before they are entitled
to the highest rating for experience
under the civil service rules. The
training school for apprentices at the
Washington Navy Yard is we'll called
the Naval Academy of Skilled Trades
There the aim of turning out good
machinists is achieved. In private
plants the apprentices are turned to
work on gu" nifty production. with
the result that the quality of produc-
ton often sadly suffers. while at the
Washington Navy Yard the product
must always be perfect to ten-thou-
sandths of an inch.
The quality of the gun factory
craftsmen can he seen from this. Dur
ing the war there were 10000 en-
ployed there, of whom $500 We're ma
chinists. Under the civil service the
less efficient were weeded out and
the cream of the trade retained. The
employees are taken in under civil
service, which picks from the top of
the list for efficiency, and the dis
charges are made from the least ef-
ficient. AS a net result of this sys.
tenn through a long period of years
the claim is made, and with some
Justice, that the best machinists in
the country are modified in this
Washington plant. There are now
about $50 machinists there.
Really there are nearly so trades
represented in the navy yard, of
which about 90 are the more highly
skilled trades. These machinists
have to be able to read complicated
blue prints and have to understand
the operation of some 80 machine
shop tools such as lathes, planners.
screw machines and drill presses, and
to use several hundred small tools
such as drills, srea mers and files. They
must know how to take care of
them and not spoil these tools, and
how to give maximum speed with due
regard for the tool and the quality Of
the work.
They must know how to use these
tools on various materials-steel. rub
Der. brass, wood, etc. They must be
able to take fine measurements down
to 900 of an inch, and to work
done to such exact measurements.
where in private machine shops