EXAMINATION BY CULTURAL METHODS 1 95 



staphylococci on the strength of an inadequate bacteriological 

 examination. For this reason we are chary of recommending 

 this method of diagnosis in any hands other than those of an 

 expert, and must urge the practitioner not to attempt it unless 

 he is prepared to carry it out properly in the most minute de- 

 tail. It is in particular absolutely useless to attempt to obtain 

 cultures with the blood taken from a skin puncture; it must 

 be drawn direct from a vein, and a large quantity (not less 

 than 5 c.c., and preferably 10) must be employed. 



One plan is to use -a hypodermic needle, and to plunge it 

 directly into a vein. The process may be carried out as 

 follows : 



Requisites. i. An all-glass hypodermic syringe of at least 

 5 c.c., and better 10 c.c., capacity, preferably furnished with 

 platino-iridium needle. 



2. Means of sterilizing the above. I personally keep the 

 syringe always sterilized with carbolic lotion (i in 20). After 

 use at any time it is washed out with the lotion, a little of 

 which is allowed to remain in the barrel, which is thus always 

 sterile. Before use the antiseptic has to be removed, and this 

 is effected by filling* the syringe two or three times with sterile 

 nutrient broth, a spare culture tube being taken for the pur- 

 pose. This g'ets rid of the waste of time involved in boiling, 

 and the necessity for carrying cumbrous sterilizers. 



Another method is to boil the instrument for ten minutes. 



Or Wright's method may be adopted. Oil is heated to 130 

 in a metal capsule, and the syringe washed out several 

 times with the hot oil. If no thermometer is at hand the tem- 

 perature of the oil can be estimated roughly by dropping a 

 crumb of bread into it. If the crumb gives off bubbles, the 

 temperature is 100 or above; it is turned brown at 130. 



3. Materials for sterilizing the skin are described under the 

 heading of Lumbar Puncture. 



4. A narrow bandage or piece of elastic, or rubber tubing. 



5. A spirit-lamp (not indispensable). 



6. Culture Tubes. On the whole broth is the most suitable 

 medium, and rather larg'e tubes, containing about 50 c.c. of 

 broth, the best to use. One or two cultures on agar should 

 also be taken. 



7. Collodion, to be applied to. the puncture after the opera- 

 tion. 



