PATHOGENES1S 289 



yet on his own surmise just fatally enough to render the animal 

 unable to cope with even a small dose of poison as 

 gradually as it would in normal days. I cannot agree with 

 Prof. Richet that he has here adopted a truly " physiological " 

 method of modifying the reaction of an animal; but I regard 

 it as an experiment in resistance to poison under conditions 

 of anaemia. The difference of point of view also marks 

 the difference of interpretation of anaphylactic phenomena 

 iu general. We have seen that Dr. A. Haig con- 

 siders life itself as very largely determined by circulation. 

 Hence, if you rob an animal of a great part of its 

 circulation, you rob it of life and of powers of resistance. 

 The principle is the same, I believe, as that whereby children 

 of tuberculous parents are rendered more "sensitive," and 

 whereby the lowering of temperature in a metal results in the 

 lowering of its electric resistance so that it now lends itself, as 

 it were, more freely to electric " intoxication " by induction. 

 The three main functions of the blood are: respiration, nutri- 

 tion, and defence against invading organisms, all of which must 

 be diminished in efficiency by bleeding. Let us see. In a 

 discourse at the Royal Institution, 2/5/13 (Nature, 31/7/13), 

 Mr. H. G. Plimmer, F.R.S., points out that the red 

 corpuscles of the blood are the carriers of oxygen, acquired 

 by the aeration of the blood in the lungs, to the tissues. They 

 are by far the most numerous, but their number varies 

 enormously under the influence of parasites (i.e., their number 

 is connected with an either physiological or pathological condi- 

 tion of the blood). Amongst the white corpuscles are the 

 Large Mononuclears able to absorb and digest parasites and 

 other foreign bodies (hence, again, on their presence in 

 sufficient numbers the general resistance of the body must 

 largely depend). The same is true of the Polynuclears. "In 

 parasite diseases these corpuscles are profoundly modified and 

 altered, numerically and morphologically, and other new 

 elements may make their appearance in the blood." (Italics 

 mine.) The numerical change easily becomes associated with 



