John’s Ph.D. research (under George Parks, completed in 1935) at Stanford University began at a time when the concept of polymers as giant molecules was just being accepted. For his Ph.D., Ferry sought to determine whether polyisobutylene, then a laboratory curiosity, had a glass temperature.1 His research also included an investigation of the temperature dependence of the viscosity of poly-isobutylene.1 It was here that he first encountered the phenomenon of viscoelasticity that was to become the central tenet of his research. On trying to turn a rod immersed in a sample contained in a tube to measure its viscosity, he was astonished to find that when the rod was released it would spin backwards. It was also at this time that he began to develop his science philosophy, which was as follows:

  1. When one has related scientific phenomena that depend on many variables, much depends on how one formulates the dependence. If one can arrange the variables suitably then some important generalizations may appear that will provide considerable insight. Thus,a researcher should set up a way of looking at the group of phenomena—a conceptual scheme— which would lead to alternating theoretical and experimental work. In addition, in the development of a science it is important to have a conceptual scheme and notation accepted by workers in the field, allowing everyone to communicate readily and to approach problems from a common general point of view.

  2. When planning experiments to answer a particular question one should make experiments not just accurate enough to answer that question, but much more accurate, if possible. Then one may not only answer the original question but also discover something entirely new.

These concepts were employed repeatedly in Ferry’s lab and led to many new discoveries.

Between obtaining his B.A. and Ph.D. degrees, Ferry went to the National Institute for Medical Research in London to learn how to make ultrafiltration membranes that could separate proteins according to size. This was the start of his



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