Correspondence, blueprints.

Correspondence between railroad engineers regarding business of subcommittee of electrical engineers, including correspondence from R. J. Wirth to L. T. Jackson regarding color of floor of subway terminal. Also includes blueprints of specification for moisture-resistant wire, specifications for portable motor-generator set for battery charging service, specifications for furnishing motor generator sets for battery charging service, specifications for series resistor box for battery charging, duct line cross sections, signal, power, telephone telegraph & communications, wiring diagram of motor-generator, battery charging set, etc.