ON THE STATE OF SOLUTION OF PROTEIDS. 223 
the subject of report that it was considered necessary to investigate its 
state of solution. 
At the outset the difficulty of preparing solutions of crystals not 
liable to pass into the condition of Methzmoglobin at the temperature of 
the osmotic experiments had to be overcome, and the work was here much 
delayed by an unfortunate accident, a newly built ‘still giving water 
holding traces of lead, which ruined all the earlier experiments. 
As the ratio of the extinction coefficients of the solutions in two 
different regions of the spectrum has been the test of the presence of 
traces of Methzemoglobin, and as no experiments have been accepted 
unless the value of this ratio agreed with that given by Hiufner, it is 
believed that the solutions finally used were free of this modification, and 
that solutions of Hemoglobin alone were used for observation of osmotic 
pressures. 
The interesting fact was soon seen that gelatine, though impermeable 
to the other native proteids used in the previous experiments, is perme- 
able slowly to Hemoglobin ; and since the ultra-microscope showed 
no more in solutions of Hemoglobin than in distilled water (again in 
marked contrast to the appearances with crystallised ovalbumin ‘solu- 
tions’), it was considered probable that osmotic investigation would prove 
a state of true solution for Hemoglobin crystals. 
When a parchment membrane was substituted for the gelatine mem- 
brane of the former experiments, it was found that solutions of crystals of 
Hemoglobin from the dog, the blood corpuscles of which bad been thoroughly 
washed to remove the serum proteids, gave remarkably constant osmotic 
pressures in relation to the concentrations, and the different values with 
different samples, so marked in the cases of the other native proteids, 
were conspicuously absent. 
The conclusion is that Hemoglobin crystals when taken up in water 
pass into a state of true solution. 
A full account will appear shortly in the ‘Journal of Physiology.’ 
Metabolism of the Tissues.—Report of the Committee, consisting of 
Professor GorcH (Chairman), Mr. J. Barcrorr (Secretary), Sir 
MIcHAEL Foster, and Professor STARLING. 
Tuer present report takes up the work which has been done under the 
auspices of the Committee since the report of 1904 was drafted. That 
report dealt chiefly with the metabolism of certain secreting glands, 
namely, the kidney and the pancreas. Respecting both these glands 
work of importance had been done in 1903-4. The scope of that work 
has been enlarged in 1904-5. 
The Kidney.—A comparison has been made between the gaseous 
exchange of the kidneys and the amount of work done in concentrating 
the urine. The ‘ work’ so done was calculated from the freezing-points 
of the blood and of the urine by Galeotti’s formula, 
It usually happens that the work of concentration increases when the 
volume of urine increases, although the urine is more dilute, but this is 
not always the case. The following experiment will show that the con- 
sumption of oxygen does not bear any relation to the work performed in 
concentrating the urine :— 
