COLLECTION OF BLOOD. 177 



dressing of a more dilute lotion for a few hours. The 

 next step is a very important one, and consists in the 

 thorough washing of the skin with methylated spirit or 

 rectified spirit ; this must' be continued until every trace 

 of the antiseptic has been removed. 



The skin is then to be punctured with a sterile 

 needle ; the stab must be a deep one and the blood 

 must flow freely. The first few drops which escape 

 must be rejected. 



The end of the pipette is then to be inserted in the 

 drop of blood and placed as near the puncture as pos- 

 sible and the blood sucked very gently into the bulb ; 

 great care must be taken lest air should gain access at 

 the same time, for it might contain bacteria which 

 might lead to erroneous conclusions. When the bulb 

 is completely filled both ends of the pipette are to be 

 sealed up. 



A much better plan is to use a hypodermic needle 

 and to plunge it directly into a vein. The antiseptic 

 precautions are the same as in the former method, and 

 the syringe and needle are to be boiled immediately 

 before use. The vein is made prominent by a bandage 

 applied firmly above the seat of puncture, just as if 

 venesection were to be performed, and the needle thrust 

 obliquely through the skin. If this method is adopted 

 there is much less chance of contamination, and the 

 difficulties of the operation are certainly no less. 



Undoubtedly the simplest and best of all methods is 

 that described by James and Tuttle (Report of the Presby- 

 terian Hospital, New York, 1898). "A piece of glass 

 tubing 4^ inches in length and J inch in diameter is 

 drawn out to a tapered end and ground to fit the cap of 

 a rather fine hypodermic needle. The larger end of the 

 tube having been stopped with a cotton plug, the whole 



