Scientific American, Vol. 6, No. 19 (May 1862)
An issue of the weekly New York patent and invention journal Scientific American, published by Munn & Co. in May 1862 for inventors, machinists and manufacturers. The plates are wood-engraved patent diagrams — cutaway magnet and cylinder bodies, hatched sectional views, a combination door-lock knob, a well-shaft hoist — each figure numbered and keyed with italic letters, giving designers crisp line-and-hatch mechanical drawing and small labelled technical vignettes.
