Diagrammatic view of an air sac Small 320×232 Medium 640×463 Large 1024×741 Download Tiff Original 2400×1737 | (280.7 KB) Description "A, epithelial lining wall; B, partition between two adjacent sacs, in which run capillaries; C, fibers of elastic tissues." — Blaisedell, 1904 Keywords air, anatomy, capillary, epithelial, lung, respiration, sac Galleries Human Lower Respiratory System Source: Albert F. Blaisedell Our bodies and How We Live (Boston: Ginn &, 1904) 172