POLLARD: That is right. It is the range with scattering. 



FANO: I think Lea's values were even lower, if I remember right, as 

 compared with other averages. 



POLLARD: They probably would be, because ours are not much lower, 

 and the scattering would certainly introduce at least, let's say, a 40 per cent 

 change. That is putting it pretty roughly. 



FRIEDELL: What was this enzyme? 



POLLARD: Solid invertase. 



BURTON: How low could you go in electron energy? 



POLLARD: The lowest effective energy is one volt. 



BURTON: Could you actually work with energies so low? 



POLLARD: Yes, in order to work with one volt you have to work with mon- 

 olayers, and this has been done by Hutchinson who really is in charge of this 

 work. If you study the action on a monolayer of bovine serum, as measured by 

 the Rothen technique in combination with the specific antibody, you can detect 

 an effect of one electron volt. 



PLATZMAN: How do you avoid electrostatic effects? 



POLLARD: I am not too sure except I know they are taken care of. It is 

 not simple. Most of the precautions that have to be taken in these things were 

 found necessary and were taken. In other words, a lot of inconsistencies oc- 

 curred until proper grids and adequate grounding and proper conductivity of 

 the surface were secured, but once these things were done, it is pretty clear 

 that you can get effects down to one volt which is rather interesting. They need 

 very large amounts of electrons. 



BURTON: How closely do you fix that one volt? 



POLLARD: To about 30 per cent. So you might say it is from 0,85 to 1 . 15 

 ev. 



KAMEN: You said there were some energy values for which there was very 

 little inactivation. 



POLLARD: If you are referring to bacterial virus, you measure the thick- 

 ness of the skin. 



KAMEN: This, I believe, was with enzymes. There was a certain energy 

 at which you got no inactivation. 



POLLARD: Yes. Well, with the preparation we use, if you are bombard- 

 ing an enzyme, not a monolayer, then there certainly is a dirt layer of some 

 kind. No matter how pure the enzyme, you will have some impurity in the ma- 

 terial on the surface. We have not been able to carry out any really low voltage 

 work except with monolayers. 



KAMEN: As far as you know, any energy whatever would have an effect? 



POLLARD: Not below one volt. Below one volt apparently the effect really 



