64 
Proceedings of Royal Society of Edinburgh. 
and tKis is accompanied by a much greater supply of blood to tbe 
organ, which is synonymous with an increased supply of material 
from which the substance is formed. 
It has already clearly been shown that a condition may be 
established in the which both kidneys will produce a similar 
result, and it is therefore difficult to imagine that this material is 
already in the blood, and is being eliminated upon one side only; 
but it is not unreasonable to consider that, if only a small supply 
of material be forthcoming, the organ which has the greater supply 
sent to it, accompanied by an increased activity in the cells them- 
selves, will produce the results described. 
1 lean to the latter view, since the quantity in which this reduc- 
ing substance appears in the left secretion is sufficiently abundant 
to lead one to expect its appearance in the right secretion, if the 
substance were circulating in that form in the blood itself. 
I therefore advance the view based upon these observations, 
that there is a distinct chemical process presided over by the renal 
epithelium which has as its result the formation of glycuronic 
acid , but the precise nature of that process and upon the presence 
of what chemical compounds it is dependent I am at present unable 
to appreciate. 
If this acid may be regarded, as is probably the case, as a deriva- 
tive of an oxidation process of the sugars within the animal 
economy, these results may prove of considerable importance as 
offering an explanation of how the sugars are oxidised within the 
system. 
These observations were made in connection with the lower 
animals, and I was thus encouraged to further pursue my observa- 
tions in regard to man. 
After a prolonged search over several hundred cases of man, 
both in disease and health, I have succeeded in finding one instance 
• — this is the first and only recorded instance, I believe — in which 
this reducing substance has been shown to be excreted in large 
quantity. 
This individual is a man about twenty-four years of age, who 
apparently enjoys perfect health and a complete sense of well-being, 
and does not suffer from any of those symptoms which but too 
readily indicate the presence of glycosuria in youth. 
