1899] TOXIC EFFECT OF DELETERIOUS AGENTS 323 
The addition of any highly ionized acid to a solution of a 
weaker acid throws back the ionization of both, but more par- 
ticularly that of the one having the low ionization. This method 
ofdecreasing the ionization, and thereby increasing the toxic 
properties, was used with di- and trichloracetic acids. To solu- 
tions of these acids HCl was added — molecule for molecule— 
_ md the resulting mixture was tested with the five molds. The 
 taltulated increase of toxic properties due to the forcing back 
if the ionization of dichloracetic acid was found to be 168 units. 
The experimental test gave an increase of toxicity for the mix- 
| lure of 147 units more than the additive toxic properties of the 
| lWo acids mixed. In the case of trichloric acid the experi- 
) mental test gave a slight excess (13 units) over the calculated 
—«*WMcrease.3 
Krénig and Paul’s (97) work on anthrax spores is of especial 
terest here. A preparation of anthrax spores immersed in a 
-; “olution of trichloracetic acid for 2 hours and afterwards 
cultured in a favorable medium proved to be entirely sterilized, 
tot a spore Surviving. In another test when a similar prepara- 
. = of spores was immersed in the same concentration for 20 
‘nutes, comparatively few survived. Tests were also made 
with the same acid at = concentration. Spores immersed in 
aes I 
- ths “encentration for 56 hours showed much less injury than 
those immersed for 209 minutes in ~ solution, thus showing 
; : I 
ag that the efficacy of the acid as a disinfectant was more 
J Yeduced than could be accounted for by dilution only. Thew 
~ "the other acetic acids, although not extensive, is quite 
: oa with the results here recorded for the molds. 
Yarocyanic acid J: 20. This poison, so 
dead : HCN 0.46.7, 
. toxic to less highly organized structures. esse 
iy, . ‘ven in minute quantities, the more pay Bt uk 
q Piysicay Pisciis, Physiological action of acids, see article by the writer 
. "Y 33263. May 1899. 
