108 



NOTU ON A METHOD OK OHTAINING IlLOOD AHEl'TICALLY 



The apparatus consists of a stout bottle of 500 c.c. capacity, fitted with a rubber 

 cork which is well fastened down and luted with parailiri wax where it is in contact 

 with the mouth of the bottle. 



Through this cork, pass two glass tubes, one reaching aliout lialf-way down tlie 

 bottle, tlie other almost flush with the base of the cork. 



The former is connected by means of rubber pressure tubing witli a large hollow 

 needle of tlie kind employed for lumbar puncture. The pressure tubing is controlled by 

 a clamp. The latter is similarly connected with a short length of glass tubing tlirough 

 which the blood is eventually added to the culture tubes. The bottle contains glass 

 beads for dcfibrinating the blood, and in its neck there is fixed a metal perforated 

 diaphragm to keep back clot. 



Method nf use. A vacuum is produced in the bottle by means of a Geryk air-pump. 

 Then a couple of test-tubes are 

 fastened over the needle and the glass 

 tubing respectively, as shown in the 

 drawing, and the whole apparatus is 

 sterilised in the autoclave under 

 pressure. 



A rabbit is now etherised, fastened 

 to a board, its chest shaved, and a 

 point selected in the sixth or seventh 

 left interspace counting upwards from 

 the costal margin. This point is about 

 liiilf-aii-ineii fiom the mid-sternal line. 

 The skin over this area is seared with 

 a hot iron. Removing the first test-tube 

 and placing his sterilised thumb against 

 the needle and about half-an-inch from 

 its point, the operator directs the latter 

 downwai-ds and to the left when it will 

 enter the base of the heart just about 

 the root of the great vessels. The - ---n- 



thumb-point pi-events the needle going 



too far. The first clamp is then loo.sened and blood readily enters the bottle which 

 is kept warm by means of a hot cloth wrapped round it. .\s tlie blood flows the bottle 

 is shaken to facilitate defibrination. When no more blood can he obtained, the rubber 

 connection is clamped and the needle withdrawn, the rabbit being usually dead by this 

 time. After further shaking, the test-tube is removed from the glass tubing, the bottle 

 is inverted and tubes of melted agar or salt agar have the blood rapidly added to them, 

 the addition being controlled by the clamp or by the thumb and forefinger. In this 

 way, even from our small Sudanese rabbits, some 14 to 18 tubes of Novy-MacNeal or 

 Nicolle's medium can be obtained, and of these one does not expect to have more than 

 two to four go bad through aerial contamination. 



I am indebted to 'Sir. G. Buchanan for the drawing and for some useful suggestions 

 as regards the technique emijloyed. 



