Solid floors : railroad bridges
A 1913 civil engineering thesis by Stuart Fransworth Kosters at the University of Illinois, surveying solid (ballasted) floor construction for railroad bridges, written for engineering examiners and practicing bridge designers. The plates are hand-inked cross sections of bridge decks showing rails, ties, ballast, concrete slabs, girders and stringers, drawn with dimension lines, hatched and stippled fills, and pen lettering that designers can lift as technical line work or annotated diagram borders.
