The design and test of a new type of telephone repeating coil
An engineering thesis by Hubert Michael Turner, submitted at the University of Illinois in 1915, on designing and testing a telephone repeating coil. The plates are hand-lettered log-log and linear graphs on tinted stock: inductance and L/R plotted against cable length, galvanometer deflection against milliamperes, with ruled grids, fanned straight-line families and typewriter-style axis labels.
