2 



METHOD OF ANALYZING THE BLOOD. 



Place it upon a chloride of calcium bath, and subject it to a temperature of from 

 220° to 230° F. until it ceases to lose weight, on being weighed at intervals of half 

 an hour or an hour, the outside of the capsule being wiped clean and dry each 

 time. Subtracting the weight of the porcelain capsule from the last weight, Ave 

 obtain the amount of solid matter in the portion of hlood evaporated, and subtracting 

 the solid matter from the amount of blood employed, we ascertain the amount of 

 water. 



To ascertain the amount of solid matter in 1000 parts of hlood, we use the follow- 

 ing proportion : — 



Weight of \ . (Weight of) -j^qqq , (Proportion of solid matter 

 blood evaporated) (dry residue) lia 1000 parts of tlie blood. 



Having ascertained the solid matter in 1000 parts of blood, the amount of water 

 may be determined by simply subtracting the solid matter from 1000. 



Next, incinerate the solid residue in a porcelain or platinum^ crucible, until all 

 the carbonaceous portion is consumed, and a light-red or yellow ash remains 

 behind. A high heat and much care are indispensable in this tedious process. 



Another method, recommended by Dr. R. E. Rogers, Professor of Chemistry in 

 the University of Pennsylvania, is to treat the dried residue with nitric acid, and, 

 gradually boiling down, incinerate. The organic matters readily dissolve in the 

 hot nitric acid, and pass off in the form of gases. 



The proportion of fxed saline matter in 1000 parts of blood may be calculated 

 in the following manner : — 



Weight of 1 . ( Weight of ash "(^ _ _ IQOO • f ^''oportion of fixid saline matter 

 blood evaporated) (after incineration) (. in 1000 parts of blood. 



From this first portion of blood, we have now obtained — 



Water in 1000 parts of blood. 

 Solid matter in 1000 parts of blood. 

 Fixed saline matter in 1000 parts of blood. 



Treatment of the Portion (h) . 



Determine accurately, with the balance, the specific gravity of the blood. This 

 should be done immediately after the porcelain capsule containing the blood is 

 placed upon the chloride of calcium bath. 



Treatment of the Portion (c). 



Ascertain the weight of the porcelain capsule and the blood which it contains, 

 and, subtracting the weight of the capsule, we have remaining that of the blood. 

 Set it aside until the blood is completely coagulated, and the serum separated from 

 the clot. The length of time required for this varies according to circumstances 

 and the character of the animal. 



Ascertain the specific gravity of the serum in the 100 grain sp. gr. bottle. 



Pour into a porcelain capsule (weight previously noted) from ten to fifty grains 



* For general purposes, a crucible of porcelain is to be preferred to one of platinum. 



