1922. ] “* Renal Portal’ System. 167 
From the three ‘‘30”, ‘«46”’, and ‘‘60” urine samples, and 
— the three ® perfusion fluids, I took naar equal quantities 
each (u mark on @ pipette ©), put these in six sma 
oplinatiecl fa of equal diameter) and added to each an 
equal quantity of the stock ferric chloride solution. 
—- perfusion fluid sample = pale transparent bluish-green =1 
ao 
a oe »» == transparent sky blue 
‘607: = deep sky blue=2 
“ 30” urine > samnple = = pale transparent bluish-green maa nd 
** 46 ish-green = 1:2 
SEO — - canintaae 1-2 
All three urine canner were then identical in color (and a little 
deeper than the aortic perfusion erry rik despite the 
rise in strength e KyFe (CN), in the 
I took six more similar samples aan "added ‘the six soy 
exactly equal quasieies : Gibeairsked covepaie sublim 
solution: this produced in each case a pinkish Salaacercs 
or 
amples and tested for f nitrogen strengths, and 
aaa “that t rratare were in the ratios of 20, 30, 40, A 
s all these re ah pw ae that 2 ne thegind the flows are correct, 
_ substitution of the stronger fluids in the renal afferent veins makes 
o difference to the KFo(CN),, KI or icone: strengths of the urine 
I performed two ore experiments (one is described in Experiment 
1, Appendix C) in both of which I tae tees: psi of KyFe 
(CN), and urea strengths of the ratios of 30, 60 and 90(!) thr ough the 
renal afferent veins and obtained results identical with those just 
described. 
ConTROL EXPERIMENT. This experiment was Ap ger with Experi- 
ment 2 just described save that the ‘‘ 46” 0077 - ids 
were perfused tabs ed the aorta fovea of areiick the r.a.v. 
The flows varied between 3-7 and 4°5: the flows in Ay ‘two 
r.a.v. bei 
30 fluid IL+IR=0-1 c.c. (15 m.) [N.E.] 
in aorta IIL+IIR = 1:1 c.c. (45 m.) = 30 urine. 
46 fluid IIIL+IIIR = 04 c.c. (15 m.) [N.E. J 
in aorta IVL+IV eo I'l c.c. (830 m.)= 46 urine. 
60 fluid VL+VR= 0-2 c.c. yrds A bas =| 
in aorta VIL+VIR= aries. (75 m.) = 60 urine. 
I pers exactly equal igen ax oe rs the three *‘ 30"’, << wid 
** 60” samples from the three perfus 
fluids and added to eac Pi “ grea sual bere _ stock ferric 
chloride solution, the results being as follo 
If we denote the colorations of the ‘*30”, “46” and ‘60’ 
perfusion ae samples, as in the last as ASD vg by the 
figures 1, 1°5, 2, then 
the color of the #s ‘30° x ' urine — was about 11 
We i ae ef », between 1-3 and 1-4 
: ime >» between 1-6 and 2 
Precipitating the KI with Giiaatesbe corrosive sublimate gave 
ilar results. 
7: 
The « nitrogen strengths of equal ap oes of os “30”, “ 46” 
and ‘* 60” perfusion fluids and the ‘:30” and ‘*60”’ 
