Ralph W. Websteb 



17 



d. Oxalates and Carbonates. — The absorption noted, when the influence of 

 oxalate and carbonate solutions is studied, is as follows: 



TABLE X 



From the above tables we see that the effect of the anions SO 4, CgO^, CO3, is much 

 different from that of the CI anion. In equimolar solutions there seems to be a close 

 analogy between the effects of the dibasic group and those of calcium salts of monobasic 

 acids. These effects were to be expected if the idea of Wallace and Cushny, concern- 

 ing the precipitation of calcium by saline cathartics, be correct. If, however, we 

 compare isosmotic solutidhs, the apparent retarding effect of the anion is replaced by a 

 favoring effect. Thus it will be observed that a muscle gains, in y'^m Nag SO 4, 4 per 

 cent in 24 hours, while in -ji^mCaClg it loses 20 per cent. 



An apparent variation from the general effect of dibasic anions is noted in the 

 case of Nag CO 3 solutions. Here we notice that a positive absorption begins, at once, 

 and increases much more rapidly than even that due to ^m KCl solution. It will be 

 remembered that Loeb found that the addition of a small number of OH ions greatly 

 facilitated the absorption. In NagCOg solution we have quite a marked hydrolysis, 

 giving us free OH ions, upon which depends the alkaline reaction of the solution. We 

 are, therefore, justified in assuming that the marked positive effect, noted in case of 

 Nag CO 3, is due to the free OH ions present in the solution. 



e. Citrates. — The results following the use of citrate solutions were, practically, 

 the same as those observed with dibasic salts. Here, again, we notice that isosmotic 

 solution (yV°^) o^ sodium citrate has a slightly favoring effect, instead of an inhibiting 

 one. Although the absorption under the influence of dibasjc and tribasic salts is not 

 at all great, yet the variation, noted in the effects of Na and K salts of monobasic acids, 

 is lost, when we observe the results of absorption under Na and K salts of polybasic 

 acids. The anion must, therefore, exert some influence on the absorption, either by 

 neutralizing the effect of the cation as in the case of Kg SO 4 or, perhaps, by changing 

 the state of the muscle plasma by the precipitation of calcium. 



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