> It must be remembered, also, that labor-saving devices, and indeed inventions of all kinds, often absolutely lessen demand instead of increasing it. Suppose,

> It must be remembered, also, that labor-saving devices, and indeed inventions of all kinds, often absolutely lessen demand instead of increasing it. Suppose, for example, that the many attempts at producing a satisfactory traction engine should result in success; is it not evident that the number of horses in use would be greatly diminished? This would similarly reduce the demand for horseshoes, horseshoe nails, currycombs, and harness of all sorts, every one of which now forms the centre of extensive manufacturing interests, employing many men. Also prescient, John Froelich got such a tractor working 14 years later!