404 JAMES HILLIER 



mounting and that auxilian- pciuipmeiit peculiar to an electron micro- 

 scope laboratory. The last includes a good quality light microscope, 

 perhaps supplemented by a microscope of intermediate quality for 

 rough work. A comparator should be conveniently available if the 

 work includes any amount of particle size measurement or electron 

 diffraction studies. Because of the recent development and M-ide- 

 spread use of the shadow-casting technique an electron microscope 

 laboratory is not complete without vacuum evaporating equipment. 

 The electron microscope laboratoiy should also include ample facilities 

 for filing negatives and prints, since these generally accumulate with 

 surprising rapidity. 



Personnel. The personnel of the electron'^^microscope labora- 

 tory can vary to a certain extent according to the organization of 

 which it is a part. A minimum requirement would appear to be a 

 trained electron microscopist and a technician or a well trained as- 

 sistant. The microscopist should be responsible for the mainte- 

 nance of the instrument and for the quality of the work produced by 

 the group. The most successful electron microscopists at the pres- 

 ent time have been individuals who have had education or experi- 

 ence equivalent to a doctorate degree or better in physics, stressing 

 optics or light microscopy. Such individuals will find some advan- 

 tage in having had some experience in electronics, but it is by no 

 means essential. It is extremely important that the electron micros- 

 copist have a thorough understanding of the general problems of the 

 laboratory in which he works. He is then able to discuss intelligently 

 the results of the electron microscope investigations and its relation- 

 ship with the research problem of the individuals providing the 

 specimens. It is obvious that the selection of the appropriate individ- 

 ual for this position is a major step toward the successful utilization 

 of the electron microscope by any laboratory. The assistant or 

 technician, on the other hand, need not have as much experience or 

 formal training. It is highly desirable, however, that that individual 

 be able to learn to make high quality electron micrographs of the 

 specimens provided and also to carry on the photographic developing 

 and enlarging that is so much a part of electron microscopic work. 



Operation. In operation the electron microscope laboratory 

 will be provided with problems from other research groups in the 

 laboratory or group of laboratories with which it is connected. 

 It will be the responsibility of the electron microscopist to comprehend 

 the type of information required for the problem and to use or develop 



