Thumb Screw Shading Small 254×320 Medium 509×640 Large 814×1024 Download Tiff Original 1908×2400 | (396.4 KB) Description A thumb screw shading illustrating a double curved surface line shading technique. Keywords Drawing Shading, Line Shading Thumb Screw Ruled Line, mechanical drawing, Shading, Shading Screw Galleries Mechanical Drawing Source: French, Thomas E A Manual of Engineering Drawing for Students and Draftsmen (New York, NY: McGraw-Hill, 1911)
