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Photographs made by photomicrography can be
examined like any other photographs and show no more texture than
will any print.

** Steel Pen Used in Draftsman's Ink Bottle Cork [117]
A steel pen makes an ideal substitute for a quill in the stopper
of the draftsman's ink bottle. The advantage of this substitute is
that there is always one handy to replace a broken or lost pen,
while it is not so with the quill.
--Contributed by George C. Madison, Boston, Mass.

** How to Make a Pilot Balloon [118]
By E. Goddard Jorgensen
Unusual interest is being displayed in ballooning, and as it is
fast becoming the favorite sport many persons would like to know
how to construct a miniature balloon for making experiments. The
following table will give the size, as well as the capacity and
lifting power of pilot balloons:
Diameter. Cap. in Cu. Ft Lifting Power.
5 ft. 65 4 lb.
6 ft. 113 7 lb.
7 ft. 179 11 lb.
8 ft. 268 17 1b.
9 ft. 381 24 lb.
10 ft. 523 33 lb.


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