CHAP. III.] THE BLOOD IN DISEASE. 151 



In man, unless suffering from grave organic disease, or subject to 

 obvious drain of blood constituents, the conditions rarely exist which 

 are requisite to induce so characteristic an anaemia; in him, indeed, 

 anaemia from hidden functional disorders of nutrition is rare, and, 

 from the less susceptible nervous organization of man, when occurring 

 in him, anaemia wears a somewhat different aspect from that which 

 it presents in the chlorotic girl. Nevertheless chlorosis may be taken 

 as the very type of anaemia depending upon a purely functional 

 disorder qf nutrition, and in discussing the changes which the con- 

 stituents of the blood undergo in anaemia, we may take as examples 

 cases of chlorosis, as they have been most frequently studied and 

 obviously present the least complicated instances of anaemia. 



It has been generally observed that in chlorosis, the bulk of the 

 clot as compared with the volume of serum is markedly diminished 

 and that usually the clot presents a buffy-coat. This appearance has 

 by some been interpreted as indicating that the blood of chlorosis 

 contains an excess of fibrin, which is not however the case. Amongst 

 the causes which may induce the appearance of a buffy-coat is un- 

 doubtedly the increase in the relative quantity of liquor sanguinis as 

 compared with the corpuscles. Thus Buchanan shewed long ago that 

 when recently shed blood is diluted with serum, the clot which sepa- 

 rates always exhibits a buffy-coat. 



If we except the diminution in the number of corpuscles and of 

 haemoglobin and the consequent increase of water, the blood in 

 chlorosis exhibits no other deviations perceptible by chemical analysis. 



The following exhibits tlie maxima, minima and mean results of twelve 

 analyses of blood made by Andral and Gavarret in nine cases of chlorosis 1 : 



Composition of Blood in 1000 parts. 



Solid 

 Water. Solid residue. Fibrin. Corpuscles. residue of 



Serum. 



Maximum 8687 .. 181*3 .. 3*6 . . 95-7 . . 100-9 

 Minimum 818-5 . . 131-5 . . 2-1 . . 38'7 . . 75-4 

 Mean 853-2 . . 146-8 . . 2-9 . . 56-7 . . 88'0 



The following table exhibits the mean composition of the blood of six 

 chlorotic girls as determined by Becquerel and Rodier. 



Density of defibrinated blood . . 1045*8 



Density of serum . . . . 1028-1 



Water . . . 828-1 



Solid constituents . . . . 171 '8 



Fibrin 3-4 



Fat 1-5 



Albumin . . . . . 72-1 



Blood-corpuscles . . . . 86*0 

 Extractive matters and salts . 



1 Simon's Animal Chemistry, Vol. i. p. 314. 



