ScientificAmerican1919-05-03.jpg Scientific American 1919-03-29ThumbnailsScientific American 1919-05-10Scientific American 1919-03-29ThumbnailsScientific American 1919-05-10Scientific American 1919-03-29ThumbnailsScientific American 1919-05-10Scientific American 1919-03-29ThumbnailsScientific American 1919-05-10

Testing the wearing quality of a tire, on a test rig located on a factory roof.