Electrical measuring instruments : grand prize Louisiana Purchase Exposition, St. Louis, 1904
A trade catalogue of electrical measuring instruments issued by the Leeds and Northrup Company of Philadelphia in 1904, following the firm's award at the St. Louis Louisiana Purchase Exposition, aimed at engineers and laboratory buyers. Halftone and engraved plates show galvanometers, resistance boxes, bridges and switch panels as isolated objects on plain grounds, with turned knobs, binding posts and polished brass and hardwood bases.
