Machinery pattern making
A technical manual on foundry pattern making for machinery, written by Peter Spear Dingey and published by John Wiley & Sons in New York in 1892 for apprentice patternmakers and shop draftsmen. The plates are outline diagrams of gear tooth profiles, arranged in grids with crossing centre lines, decimal dimensions and italic captions giving tooth counts and pitch in inches; useful for repeatable silhouette shapes, measured-drawing layouts and small numeric annotation.
