322 CIRCULATING FLUIDS: 



with etlier yields a small quantity of solid fat. The decrease in 

 the density of the serum at this stage is very remarkable. While 

 in healthy blood it is estimated at 1029 — 1031, it now sinks to 

 1020, or even 1019 ; and in connexion with this cu'cumstance 

 we find a large quantity of albumen in the urine. 



Another very remarkable peculiarity is the presence of a cer- 

 tain quantity of urea in the serum. 



The following changes occur in the progress of the disease : 

 (1.) There is an excess of serum, the clot often constituting not 

 more than one fourth of the blood. (2.) The density of the 

 serum returns to its normal state, or even exceeds it ; some- 

 times, however, it remains low, even in the advanced stages. 

 (3.) The urea disappears as the disease advances, but usually 

 reappears, towards the termination of the case, in even a larger 

 amount than pre\dously. (4.) The fibrin, which is increased 

 in the first stage, returns to its normal amount as the disease 

 advances, and only becomes considerable again during inflam- 

 matory complication. (5.) The most remarkable character of 

 the blood in the advanced stage is the great decrease of blood- 

 corpuscles, which frequently amount to only one third of the 

 normal proportion. 



I have analysed the blood in four cases of Bright's disease, 

 and obtained the following results : 



The blood in analysis 36 was taken from a man aged 40, who 

 had been treated for some time in our hospital for this disease : 

 traces of urea were detected in the extractive matters, by the 

 method given in page 183. — The blood in analysis 37 was taken 

 from a man aged 20, Avhose feet and arms were so cedematous 

 as to render venesection a matter of some diflficulty. Consider- 

 able quantities of urea were found in the blood. — The blood in 

 analysis 38 was taken from a man aged 30, in whom the dis- 

 ease was not so advanced as in the former cases. A consider- 



