80 BLOOD. 



4. Shake the blood-corpuscles thus freed from serum 

 with ether and water, and observe that the red hema- 

 tocrystalline dissolves in the water. Filter this solution 

 without delay, and expose to a low temperature. If 

 the blood came from dogs, rats, guinea pigs, or squir- 

 rels, it will crystallise at once, but if it came from 

 birds will crystallise only after the addition of one 

 quarter of the volume of the solution of alcohol of 80% 

 strength, and exposure to a cold of from 5 to 10 0. 

 Separate the crystals by nitration, wash with alcohol 

 of 20% strength by volume, press them between fil- 

 tering paper, redissolve in a minimum of water, filter 

 again, mix with one quarter volume of alcohol of 80%, 

 and expose again to the low temperature. The crys- 

 tals of hematocrystalline will re-form in a purer state 

 than before. If the blood employed in this process be 

 human or veterinary, no crystals, but only an amor- 

 phous deposit of hematocrystalline, will be obtained. 



5. Burn a quantity of these crystals in a platinum 

 crucible and observe that they leave a quantity of 

 red iron oxyde corresponding to 0*43% of metallic 

 iron in the crystals. Determine the other elements 

 and observe that all analyses lead to the formula 

 c coo HOGO N i5i Fe S s 177 , giving an atomic weight of 

 13280. 



6. Place a concentrated solution of hematocrystalline 

 in a test-tube before the slit of the spectroscope, and 

 observe that it excludes all light but the red. Then 

 dilute the solution with water, and observe that green 

 and blue light passes, while in yellow and the 

 beginning of green a dark space remains. On further 



