An introduction to the theory of electricity, with numerous examples
A physics textbook by Linnaeus Cumming, published by Macmillan in London in 1876 to teach electrical theory to students through worked examples. The line engravings are geometric diagrams: lettered triangles and ellipses with hatched shading, coils and plates wired into circuits, cones of lines converging on rings, all crisp black-on-white forms usable as abstract marks.
