The structure of fibrous proteins of the collagen-gelatin group

Collagen is a very interesting protein. It has well-defined mechanical properties (great strength, reversible extensibility through only a small range) that make it suited to the special purposes to which it is put in the animal body, as in tendon, bone, tusk, skin, the cornea of the eye, intestinal tissue, and probably rather extensively in reticular structures of cells. During the last thirty years, following the pioneer work of Herzog and Jancke,(1) a number of investigators have attempted to find the structure of collagen (and of gelatin, which gives similar x-ray photographs), but no one has previously proposed any precisely described configuration, nor has attempted to account for the positions and intensities of the x-ray diffraction maxima