Jamison, Alpha Pierce. [from old catalog] · New York, J. Wiley & sons; · leaf 240
the stencil onthe lines representing the edges and part way through on thebase-lines; with the stencil in position, fold back the lower right-hand triangle and stipple the exposed surface rather dark; nowfold back the bottom triangle—the first remains open—and shadethe exposed area; next fold back…
Mechanical drawing
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
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