Historical Caliper Diagram - Engineering Drawing with Component Labels #1433142 (License: Personal Use)

This black-and-white technical drawing depicts a precision external caliper with dual jaw assemblies, a central pivot (labeled J), and fine-adjustment mechanisms (e.g., screw M and lever L). Cross-sections reveal internal construction details including spring-loaded contacts (F, G) and guide rails (D, H), illustrating how measurement stability and repeatability were achieved in pre-digital instruments. The labeling follows standard 19th-century patent drafting conventions.

Used on museum archives, engineering history blogs, or tool restoration guides to illustrate the evolution of measuring instruments; serves users researching antique metrology tools or seeking reference for replicating vintage calipers.