IQ08] 



PO,\n—SOLUTION TKNSION AXP TOXUITV 



23R 



in the former. It is of course simply a matler of judgment how such 

 resuUs arc to be interpreted. Since barium and strontium are e([ui- 

 toxic in contemporaneous tests and since the same is true of barium 

 and magnesium, it is reasonable to conckide that the tiiree salts arc 

 equitoxic. This same relation was found in the case of ethyl butyrate. 

 In this table (\') the control figure is higher than that in Table IV. 

 There is, however, a corresponding increase in the figures in the 

 enzyme column. Just what causes such fluctuation from day to day 

 is dilTicult to tell, but there seems to be sufficient uniformity in the 

 test as a whole. For the sake of assurance another test was made, 

 and this gave practically identical figures with those in Table IV. 

 The figure for ;»/8 barium shows some irregularity in this next table. 



TABLE VI : Barium and magnesium in contemporaneous test 



BARIUM 



Enzyme 0.05 per cent. Incubation 5 hours at 40 C. 



Tn the work with ethyl butyrate I found barium, strontium, and 

 magnesium to be equitoxic with each other, but all were more toxic 

 than either sodium, potassium, or lithium, which latter were equitoxic 

 with each other. In the foregoing tables there arc some indications 

 that barium, strontium, and magnesium are more toxic than the 

 sodium, potassium, lithium group. On the other hand, the differ- 

 ences between hthium and magnesium are not so great. Thus, w/8 

 of lithium in Table II allows 0.09, while m/16 of magnesium in Table 

 IV allows 0.07. Again, w/8 of lithium in Table III allows 0.07. 

 From the foregoing tables it would be impossible to say that the barium 

 group is more toxic than the sodium group on the equinormal basis. 



