BLOOD EXAMINATION. 75 



If the methylene green precipitates add more acid 

 fuchsin. 



Eosin .5% solution in 70% alcohol. 



Loeffler's methylene blue. 



Ehrlich's eosin-haematoxylin stain, 



Haematoxylin ... 4-5 parts 



Alcohol, glycerine, and water . 100 " each 

 Glacial acetic acid . . 20 " 



Alum to saturation. 



Allow to ripen in sun 5 or 6 weeks, and add 1% of 

 eosin. 



In blood examination the points to be ascertained 

 are the specific gravity, the amount of haemoglobin and 

 the number and characteristics of the red and white 

 blood cells. Examination bacteriologically by cover 

 glass preparations and cultures may also be required. 



The blood may be obtained from the lobe of the ear, 

 root of the finger nail or the ball of the finger, the first 

 being undoubtedly the best situation. The part should 

 be washed with soap and water, then with a mixture of 

 alcohol and ether before puncturing. The first drop of 

 blood which exudes should be wiped away with sterile 

 gauze. No pressure should be made to obtain the 

 blood. 



Specific Gravity. Allow a drop of blood to fall into 

 a cylindrical vessel containing the benzol-chloroform 

 mixture. If it floats add more benzol, if it sinks add 

 chloroform, till the drop remains stationery about the 

 middle of the fluid. Take the specific gravity of the 

 mixture and this will be the reading for the blood. 



