The Scientist and the Engineer 67 



plore all the ramifications and implications of his basic 

 experiment. 



It would be a mistake to get the impression that the 

 scientists who came after Loewi had nothing to do but apply 

 his technique. With the insight of genius he had actually 

 selected what is probably the easiest case for demonstrating 

 the phenomenon. His followers had to develop more com- 

 plicated and often more ingenious techniques when they 

 tackled the problem in warm-blooded forms, and in organs 

 which are more difficult to perfuse than are frog hearts. 



To get back to our theme of the relationship between 

 engineering and science, we may now observe that the 

 development of the techniques necessary to demonstrate 

 Loewi's phenomenon in other species and in other organs 

 involved the solution of a series of what in one sense are 

 almost pure problems in engineering. Appropriate devices 

 had to be built for providing artificial circulation to a wide 

 variety of organs. Other devices had to be built for record- 

 ing the mechanical or electrical activity of these organs. 

 Indeed, if you had watched most of this group of workers 

 on many of their working days, it would have been hard 

 to say why they weren't doing exactly what engineers do. 

 As a matter of fact some of them were and are engineers 

 by taste and by training. 



The cooperation of electrical engineers became especially 

 important when attention turned to the difficult problem of 

 nerve-to-nerve transmission, since the best way of telling 

 whether nerves are active is to record the electrical currents 

 they generate. These currents are very small and of rela- 

 tively short duration. Highly refined amplifier circuits and 

 sensitive oscillographs must be used to observe them accu- 

 rately. Much of the basic technology could be borrowed 

 from circuitry developed for other purposes, radio and TV 



