90 TISSUE FERMENTS 



In addition to the above it has been discovered that the 

 alkaline earths as well as phosphorus, as above stated, hasten 

 autolysis 47 ; arsenic, 48 quinine 49 and quite a number of 

 other drugs manifest, at least when present in considerable 

 quantities, an inhibitory influence. Many drugs seem to 

 accelerate in very small dosage, but to inhibit when in higher 

 proportions. 



The influence of colloidal metals 50 in stimulating auto- 

 lysis, made known by observations of Ascoli in Pavia and 

 his associates, seems to the author worthy of much con- 

 sideration. Eecently a contribution by C. Neuberg and 

 Caspari has attracted considerable attention, dealing with 

 the results obtained in treating mouse cancers with colloids 

 of the heavy metals. A very rapid softening and liquefac- 

 tion of the tumors was produced, and in a number of cases 

 actual tumor destruction was attained, apparently without 

 danger to the life of the experiment animals (v. Vol. I of this 

 series, p. 555 f, Chemistry of the Tissues). One cannot but 

 hesitate to spoil the pleasure this fine result inspires by 

 stating the fact that mouse cancers are incomparably more 

 benign than the analogous tumors of man (a point which 

 Wassermann explicitly brings out in warning against em- 

 ploying the method in human therapy, in an article announc- 

 ing a similar result attained in animals by the use of selenium 

 preparations). 



There is food for further thought in the fact that 



47 L. Launoy, C. R. Soc. de Biol., 62, 487, 1907; L. Briill (V. Noorden's 

 Clinic, Vienna), Biochem. Zeitschr., 29, 408, 1910. 



48 L. Hess and P. Saxl, Zeitschr. f. exper. Pathol., 5, 89, 1908. 



*"E. Laqueur, Arch. f. exper. Pathol., 55, 240, 1906; cf. also Biochem. 

 Centralbl., 8, 564, 1909; Centralbl. f. Physiol., 22, 717, 1909; G. Izar (Ascoli's 

 Lab., Pavia), Biochem. Zeitschr., 21, 46, 1909. 



80 M. Ascoli and C. Izar, Biochem. Zeitschr., 6, 192, 1907; 7, 142, 1907; 10, 

 356, 1908; 14, 491, 1908; 17, 361, 1909; L. Preti, Zeitschr. f. physiol. Chem., 

 58, 539, 1909; 60, 317, 1909; G. Izar, Biochem. Zeitschr., 22, 371, 1909; M. 

 Truffi, ibid., 23, 270, 1910, and earlier publications from the same laboratory. 



