Viewing page 25 of 230

This transcription has been completed. Contact us with corrections.

[[encircled 18]]
[[double line frame around illustration]]

PL.7.
[[image: mounted on top of a large framework workbench is a large wheel "A" connected to a hand crank.  At the hub of the wheel is a cog wheel "P" engaging a flat, geared track (rack and pinion) "C" on the top of the bench.  The rack is connected to bar "D" which the rack moves back and forth as the crank is turned.  Also attached to the bar is a twisted strip of metal "E" passing through a tool "F."  Two stops on the bench top are labeled "G."

[[double line across page]]

H
[[image: side view of a long piece (rod) of metal with four protrusions at one end\\

I
[[image: rectangular piece of metal]]

K
[[image: end [cross section) view of "H" a metal rod in four quadrants with four protrusions on the circumference]]

Transcription Notes:
mandc: gun barrels were difficult to make and more difficult to "rifle" [grooves cut into the interior surface which would cause the bullet to spin as it left the barrel. https://www.quora.com/How-were-musket-barrels-manufactured-in-the-early-modern-era