Induction motors in concatenation
An undergraduate electrical engineering thesis submitted in 1907 by Robert Owen Friend and Vernon Leo Hollister at the University of Illinois, testing induction motors wired in concatenation, and read by faculty examiners. The plates are hand-lettered test plots inked onto green and yellow printed graph paper, with efficiency and power-factor curves, plotted data points, and tabular data showing through from the reverse; useful for grid textures, draughtsman lettering, and plotted-curve motifs.
