1910] LIPMAN—LACK OF ANTAGONISM IN SALTS Ag . 
It may be of interest to note here that B. subtilis from a 24-hour 
peptone agar slope culture was examined in hanging drops of molec- 
ular solutions of calcium chlorid and showed no perceptible ill- 
effects from the action of the solution. The ciliary movements 
appeared normal even after 24 hours in the hanging drop. It was 
noticed, however, that there was little or no division among the bacilli 
during the 24 hours, and it is likely that the calcium and magnesium 
salts exercise their toxic effects by inhibiting reproduction, since 
the ciliary movements seems to go on without interruption. These 
remarks, however, are based on too meager experimental evidence 
to partake of anything else than the nature of conjecture, but 
they serve to indicate a field of most interesting possibilities in 
research. 
Though they are not analogous instances of the lack of antagonism 
between calcium and magnesium as shown above, it is interesting to 
note two cases on record, in which the addition of one salt to another 
made a combination more toxic than either. One case is that of 
Ostwa.p’s'4 experiments on the fresh-water Gammarus, in which it 
was found that a combination of MgCl, and NaCl in solution was 
more toxic to that animal than NaCl in solution alone. The other 
case is that noted in the experiments of PaAut and KR6nic,"’ who 
found that the value of mercuric sulfate, acetate, and nitrate as 
disinfectants was enhanced by the addition of small amounts of the 
chlorids of potassium and sodium; but, on the other hand, the 
addition of the same chlorids to HgCl, reduced considerably the 
disinfecting power of the latter. The first instance is not analogous 
to my results, because one of the salts used by Ostwa tp was different 
and the experiment was carried out under conditions so totally differ- 
ent that the value of a comparison here is doubtful. In the second 
instance, as PAuL and Krénic themselves suggest, the increase of 
toxicity is not necessarily owing to a lack of antagonism between the 
‘wo salts, but rather to the formation of complex double salts of 
mercury, characteristic of that element, and therefore this again 
“annot be compared with the lack of antagonism between calcium and 
magnesium above noted. 
“4 Univ. Calif. Publ. Physiology 2:163. 1905. 
'S Zeitschr. Hyg. und Infectionskrank. 25:57. 1897. 
