DEM. | 60 
rage, than a medicament, can be presenied to the 
diseased urethra after traversing the circuitous 
track of the circulatory, absorbent, digestive or 
secreting vessels, or perhaps the whole of them, 
in its pristine state of viscidity? Surely such an 
idea is not tenable. True it is, as Dr. Murray 
has observed, the secreting vessels do some times 
render substances which have been thus digested, | 
absorbed, and acted on by the secretory viscus, in 
this state of pristine character; and it cannot be 
doubted from the evidences given in the urine of 
this fact, that the kidnies especially do this: but 
the subjects they select for this preservation of 
individuality of property, are widely different in— 
nature from the bland oils andgums. It is when : 
very active substances, characterized by the inten- 
sity and persistance of their distinguishing property — 
is presented to their secretory office. And for the — 
most part it is the colouring matter, or odoriferous, 
or saline quality, that mainly appears unchanged in — 
. the secretion of the urine. The same observation — 
‘is applicable to the excrementitious evacuations, — 
after certain active or strongly marked aliments or — 
medicines have been taken into the stomach; and — 
also to the transpiratory office of the skin. I 
am aware indeed, that when gum-arabic has been 
given in considerable quantity to infants and child- — 
ren, as is frequently done, the gummy nature of the _ 
article is detected in the discharges per anu > 
a circumstance which has led Dr. Paris to a very 
mcorrect pronunciation of the insusceptibility of 
pure gum lexeaiton he says with the bitter princi- 
ple!) to yield to the assimilative functions: and | 
misquotes in corroboration of this remark the assef- 
tion of a late author,* that “it frequently pass 
through the bowels, very little changed, as 1 hay 
* Dr, Chapman. 
