128 FOURTH REPORT — 1834. 



stances. But Blundell's experiments prove, that diminution of 

 quantity is not so immediately hurtful to life as alteration of the 

 quality of the blood. Three fourths or more of all the blood in 

 the body may be removed, and the animal still live. When a 

 Dog had been rendered apparently dead by the loss often ounces 

 of blood, it Avas recovered bj'^ transfusion of two ounces. This 

 vital influence of the blood is shown by Prevost and Dumas to 

 depend not so much upon the serum as upon the red particles. 

 An animal bled to insensibility, is not revived by serum of the 

 proper temperature, but is by blood from which the fibrin has 

 been removed by stirring. But with respect to qualitj'^, changes 

 of this, slight in appearance, produce important effects. Blundell 

 found, that when he had drawn blood from a Dog's artery, and 

 reinjected it into a vein before coagulation had commenced, (per- 

 forming the operation until more blood had been thus transfused 

 than equalled the whole weight of the animal,) though it reco- 

 vered, it was ill for several days with oppressed respiration and 

 impeded action of the heart. When an animal, therefoi'e, is re- 

 vived with blood of another of the same species, we may sup- 

 pose that the operation is not entirely without danger of ill con- 

 sequences. But when this is effected with blood from an animal 

 of a different genus, the consequence is generally fatal. Of dogs 

 revived with human blood, some died shortly after the operation, 

 some on the following, others on the sixth day. When Pre- 

 vost and Dumas transfused Calves' blood into Kittens or Rabbits, 

 they seldom survived the sixth day : the pulse becoming quick, 

 the warmth diminished, the evacuations bloody. The transfusion 

 of the blood of an animal of another class, i.e. with differently 

 shaped globules, almost always causes death. If blood with 

 round particles be injected into the veins of a bird, it dies with 

 symptoms of poisoning from substances which act on the ner- 

 vous system*. 



With respect to transfusion we cannot but assent to the fol- 

 lowing judicious observations of Burdach. The blood of every 

 creature is in as special a relation to it as are any, the most im- 

 portant, organs of its body, and is its own production as much 

 as they are. It is vmder the necessity of making its own blood 

 for its own purposes . When an animal, therefore, is saved from 

 death by means of transfusion, it is saved by a mode which in- 

 troduces into its system causes of derangement in all its func- 

 tions, and which it must throw off by its powers of secretion be- 

 fore healthy action can be restored. 



Nysten's experiments, and those lately detailed by Majendie 

 in his lectures t, seem to prove, that air injected into the veins 



• Dieffenbach, quoted by Miiller. t Lancet, No. viii. 1834. 



