BY DR. BURDON-SANDERSON. 2l9 



at an obtuse angle, so that the last few inches are horizontal. 

 A little above the bend there is a bulb: the horizontal part is 

 firmly supported on a block. With this tube the recipient is 

 united either by a mercurial joint (i) or by a connector of vul- 

 canized India-rubber, inclosed in a glycerin chamber. The 

 recipient is a large glass tube (j), of about an inch and a 

 quarter diameter, and forty inches long. At its lower end it 

 terminates in a capillary tube, which is guarded by a stopcock 

 (L). Its capacit}' is about 250 centimetres, consequently six- 

 teen times that of the blood it is intended to receive. 



In selecting a method of transference, preference ought to be 

 given to those plans which are least complicated and most rapid 

 in execution. The method I have found to answer is as fol- 

 lows: The animal having been secured, a canula fitted with an 

 India-rubber connector is inserted in the vessel, which is closed 

 by a clip lege artis. For receiving the blood as it flows from 

 the artery or vein, a straight-glass tube (Fig. 199, M) of known 

 capacity is used ; one end of this tube is guarded by a stop- 

 cock, while the other is drawn out, and so formed that it can 

 be accurately stopped by the finger. A trough having been 

 filled with mercury, completely freed from air by passing 

 through the pump, the narrow end of the tube is dipped into 

 it. The tube is then easily filled up to the stopcock by aspira- 

 tion and the stopcock closed. It having been ascertained that 

 the tube is perfectly full, it is placed in an inclined position, 

 with the stopcock end downwards, and the open end at such a 

 distance from the canula that the India-rubber tube can be 

 easily slipped over it at the required moment. This having 

 been accomplished, and the other end of the tube having been 

 fitted with a bit of India-rubber tubing of sufficient length to 

 convey away the mercury to a convenient receptacle, all is 

 read3'. The clip on the canula is opened, and blood allowed to 

 flow freely from the tube for a few moments while the mercury 

 tube is grasped by the operator. The warmth of the hand 

 causes the mercury to expand and project from the open end 

 of the tube: at that moment the India-rubber connector from 

 which blood is flowing is slipped over it, and the connection is 

 completed without the slightest risk of the introduction of air. 

 Without a moment's loss of time the stopcock is opened, and 

 the blood allowed to replace the mercury. The stopcock having 

 been closed, the India-rubber connector is slipped off, and the 

 open end of the tube closed with the finger. The tube is now 

 placed with its open end downwards in the mercurial trough 

 (u), the finger being still kept on the orifice, while an assistant 

 fills the bit of capillary tube beyond the stopcock with boiled 

 distilled water, and connects it with the corresponding end of 

 the recipient by means of an India-rubber connector. The mo- 

 ment that this is accomplished, the finger is removed from the 

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