13. At the opposite end of the bar _E_ is
placed a looped spring _G_, which carries a steel tube and point like
the spring _D_, Fig. 14. Above this tube and point, shown at _j_, Fig.
15, is placed an adjustment screw _k_ for fine adjustment. The inner end
of the screw _k_ rests against the end of the bar _E_. The tendency of
the spring _G_ is to close upon the end of _E_; consequently if we make
use of the screw _k_ to force away the lower end of _G_, we can set the
fine point in _j_ to the greatest exactness.
The spring _G_ is made of a piece of steel one-eighth of an inch
square, and secured to the bar _E_ with a screw and steady pins at _m_.
A pen and pencil point attachment can be added to the spring _G_; but in
case this is done it would be better to make another spring like _G_
without the point _j_, and with the adjusting screw placed at _l_. In
fitting pen and pencil points to a spring like _G_ it would probably be
economical to make them outright; that is, make the blades and screw for
the ruling pen and a spring or clamping tube for the pencil point.
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