Experimental Inquiry concerning the question, whether the Purgative
Action of the Neutral Salts is the effect of Enclosmosis ? By Dr. II.
Aubert.—Aubert made bis experiments with the purpose of examining
the correctness of the view spread under Liebig's authority (“ Unter-
suchung der Mineralquelle zu Soden und Bemerkungen ueber die Wirk-
ung der Salze auf den Organismus”—Wiesbaden, 1839), that the pur-
gative action of the neutral salts is a merely physical process, being the
consequence of cxosmotical transudation from the walls of the intestinal
tube, effected by the more concentrated solution of these salts within
the cavity of the tube. The experiments were instituted in the follow-
ing manner:—Solutions of different neutral salts were put into a cylin-
drical glass tube, the lower end of which was covered with a piece of
membrane, from a pig’s bladder; then the tube was immersed into
serum of blood, and the changes going on in the solution within, and the
serum without, were examined at different intervals. Another series of
experiments were made by taking internally solutions of these salts. As
the result of both series, Aubert draws the following inferences :
1. The purgative effect is not influenced by the degree of concentra-
tion of the solution ; the number of stools produced by a certain quantity
of salt will be the same, whether the salt is dissolved in six or seventy-
two ounces; the water of the solution is excreted by the kidneys ; the
salt exercises its influence on the bowels. 2. No albumen is found in
the alvine excretions, as ought to be the case, if the action of the salts
was an endosmotical one. 3. The quantity of salt excreted through the
urine, compared with the quantity of water contained in the discharge
from the bowels, is not that which it ought to be, according to the laws
of endosmosis and exosmosis (as much, at least, as they are known at
present). 4. Peristaltic motion of the bowels is constantly excited by
the neutral salts; the rolling and rumbling, which Aubert always ob-
served soon after taking the salts, as well in a concentrated as when in
a diluted solution, is attributed by him to the action of the salts on the
nerves of the intestines, and to the reflex motion excited in consequence
of this. 5. A part of the sulphate of magnesia appears to be decom-
posed within the organism, as the magnesia is excreted in a larger pro-
portion than the sulphuric acid with the faeces; the sulphuric acid in a
larger one than the magnesia with the urine. 6. The remedy produces
the characteristic effect on the bowels, when a solution of it is merely
infused into the veins of an animal.
It must be, however, remarked here, that Liebig himself, in a work
of a later date, (f Untersuchuugen ueber einige Ursachen der Saeftebe-
wegung im thierischen Organismus,” 1848,) states, that he does not in-
tend to explain the whole action of the neutral salts by endosmosis, but
that he considers this to be one of their influencing qualities.—Ibid ,
from Ilenle und Pfeiffer's Zeitschr. fur Ration. Medic.