EDITORIAL. 
287 
tion. Thus, for instance, in the attempt to form a conclusion regarding the 
metamorphosis of the blood from an elementary analysis of its solid residue, 
and of the composition of the individual constituents of the excretions, there 
is an utter absence of all scientific ground work ; for, independently of the 
fact that the elementary analysis of so compound a matter as the blood is 
incapable of yielding any reliable results, and cannot, therefore, justify the 
adoption of any special chemical formula, it is assuredly most illogical to at- 
tempt to compare the composition of the blood collectively, with that of the 
separate excrementitious matters." Page 3, 4. 
Whilst acknowledging the indebtedness of the physiologist to the chemist, 
he remarks : 
" Animal chemistry is still wholly unable to afford us a precise, and at the 
same time a practically useful method of investigating the blood ; and how 
should it be otherwise while we continue to be in doubt regarding the chemi- 
cal nature of its ordinary constituents % The mineral substances of normal 
blood are not yet determined, or, at all events, continue to be made the subject 
of dispute. We scarcely know the names of the fatty matters it contains ; 
one of its most important constituents, fibrin, cannot be chemically ex- 
hibited in a pure state ; we are ignorant of the nature and mode of secre- 
tion of the globulin of the blood-corpuscles ; we are still far from being able 
to separate and determine the so-called protein oxides ; and we are also 
ignorant of the excrementitious substances occurring in the blood. How 
then, amid these and a thousand other uncertainties and doubts, can an in- 
vestigation of the blood be scientifically and trust-worthily conducted % We 
analyze healthy and morbid milk ; and yet we are ignorant of the substances 
whose admixture we call casein. The urine, in its morbid condition, presents 
many varieties ; and yet our knowledge of this secretion, frequently as it has 
been analysed, amounts to little more than an acquaintance with the quan- 
titative relations of some of its principal constituents ; creatinin and hippuric 
acid have not been determined by an analysis, and doubts are still enter- 
tained by some chemists, (although most unjustly,) regarding the pre- 
sence of the latter in human urine, whilst nothing absolutely is known 
regarding the most important pigment of this secretion. Many experi- 
ments have been made, and theories broached on nutrition and digestion, 
and yet to almost the present day the existence of lactic acid in the gastric 
juice has been contested. Although hypotheses are not wanting regarding 
the mode of action of pepsin, we know nothing of its chemical nature, 
and we are wholly ignorant of the proximate metamorphosis of albumin- 
ous bodies in the stomach during the process of digestion. Will Mulder 
be able, even with his most accurate analyses, to support his protein theory 
by the aid of sulphamide and phosphamide % Or is this term destined 
merely to indicate a past epoch in organic chemistry % When such is the 
state of animal chemistry, can we wonder that there should be obscurity 
regarding the chemical processes in the animal body, their various isolated 
and combined actions, their casual connexion and their dependence on ex- 
ternal influences and internal conditions'?' 5 
Our author then goes on to show that the organic substrata of the animal 
body (the proximate constituents and their derivatives,) should be thorough- 
ly understood before venturing an opinion on the nature of the processes . 
For this reason the first volume of his work is devoted to the description 
