Genetics and Microbiology 27 



the chemostat, in which cultures can be maintained in a 

 self-regulated, steady-state environment long enough to 

 submerge short-term random fluctuations. Accordingly, 

 spontaneous mutations can be measured with a precision 

 of 5 to 10 per cent and an assurance that nonlinear per- 

 turbations of the steady state are either self-cancelling or 

 so exaggerated as to be self-evident. Sophisticated studies 

 of bacterial mutation can no longer afford to ignore the 

 experimental control uniquely offered by this approach. 



"Experimental control of spontaneous mutation" is an 

 intentional paradox. "Spontaneous," despite purposeful 

 misreading by dialectic materialists, means neither the im- 

 materiality of the gene nor the notion that genetic ma- 

 terial lacks a physical nexus with the environment (19). 

 It does mean that the subtle chemistry of the gene has 

 evolved through conservative mechanisms so refined that 

 we cannot discern their connection with the end products 

 of organic structure and function; at least we have not 

 yet learned how to distinguish one gene from another by 

 reactants that allow purposeful, specific changes. Some day 

 the secret of specific mutagenesis will be revealed, but such 

 faltering claims, for example, as that antibodies might 

 alter specific genes have not held up (42). To my mind, 

 the search for this philosopher's stone by bludgeoning the 

 bacterial gene with drugs or enzyme inhibitors will some 

 day seem as credulous as the snipping of mouse tails does 

 now, and it has already had equally negative, if sometimes 

 glittering, results. [I cannot overlook the remarkable effects 

 of one inhibitor, acriflavine, on respiratory factors in yeast 

 (13), but this seemingly embarrassing exception has illu- 

 minated the path from infection to heredity (9, 28) — the 

 effect is akin to the "chemotherapeutic cure" by strepto- 

 mycin of green plants with regard to their chloroplasts 

 (41, 48).] 



Experiments with the chemostat have demonstrated sig- 

 nificant environmental control over rates of sporadic muta- 



