98 OTTO GLASER. 



This assumption involves on the part of enzymes or organic co- 

 enzymes a capacity for combining with heavy metals. Since this 

 power is not only very great, to judge by the dilutions that in- 

 capacitate, but likewise inseparable from normal ferments, we 

 should not be astonished if enzymes from copper-bearing organ- 

 isms or tissues give positive results when tested for copper. 



3. The Oligodynamic Effects of Copper. 



The poisonous effects of extraordinarily high dilutions of metal- 

 lic copper were first noticed by Nageli ('93), who found one part 

 in seventy-seven millions rapidly fatal to Spirogyra. Because of 

 the extremely small quantities involved Nageli spoke of " oligo- 

 dynamic action." 



As these results have been repeatedly verified on other forms, it 

 may be convenient to retain Nageli's term. However, "oligo- 

 dynamic" need imply nothing more mystical than a chemical or 

 perhaps physical relation between extremely small quantities of 

 material. As yet no acceptable explanation has been offered. 5 



But there have been suggestions. Nageli was able to destroy 

 the toxicity of oligodynamic solutions by means of paper, wool, 

 paraffin, gums, and gelatin. The experience is quite comparable 

 to the protective action of egg-water, gum arabic, and gelatin de- 

 scribed by Lillie ('21 2 ). Inasmuch as the copper in the first case 

 at least is probably present as electropositive colloidal hydroxide 

 or carbonate, Bayliss ('15 2 ) imagines adsorption on the electro- 

 negative surfaces of Nageli's detoxicants as the basis of their anti- 

 toxic properties. Conversely, the toxic effects become explicable 

 as the outcome of adsorption by electronegative surfaces or parti- 

 cles critically involved in or on the affected tissues. 



At this point Bayliss leaves the problem. We still do not know 

 why such minute quantities are effective. Do they cause precipi- 

 tation? If so, how much precipitation can they conceivably bring 

 about ? And, finally, what is precipitated ? The neutralization of 

 electrical charges in all likelihood is unavoidably associated with 



5 Quite recently, Saxl, as quoted by von Euler and Svanberg, assumed " dass 

 die Metalle eine eigenartige Keimtotende Kraft besitzen, welche nicht mit der 

 Loslichkeit der Metalle zusammen hangen soil." Saxl refers to a physical 

 energy "die sich zunachst auf der Oberfiache der Metalle abspielt, jedoch 

 auch in andere Medien iibergehen kann " ('20 2 p. 378). 



