Elements of aviation engines
A 1918 instructional manual on aircraft engines by John Baptiste Ford Bacon, published by Paul Elder and Company in San Francisco for wartime mechanics and flight students learning ignition and motor practice. The plates are spare black outline diagrams on cream stock: coil windings drawn as rows of loops and zigzags, magneto rotors as wedges and arcs on a pivot, and simple wiring schematics, useful as flat geometric marks, repeating pattern strips, or diagram-style ornament.
