Thomas machines constitute a branch point in the evolution of calculating machines. Until this time, commercial and scientific success had been twin goals -- design and construction rested in the hands of scientists, mathematicians and mechanicians. The industrial revolution somewhat changed the picture. Professional mechanists were developing their skills in techniques of mass production. One path followed the perfection of inexpensive, reliable machines for commercial use. Following the other, scientists dreamt of a machine that would reach further into the complexity of mathematical thought.