Design and construction of a muffler
An engineering thesis on muffler design and construction submitted by Frank Earl Sperry at the University of Illinois in 1910, prepared for faculty examiners in mechanical engineering. The plates are hand-inked charts on printed orange-brown graph paper: fanned families of curves for air flow through orifices of stated fractional diameters, labelled axes in typewriter capitals, and a crossing-line diagram of pressure and volume against exhaust stroke intervals.
