34 Transactions. — Miscellaneous. 



property possessed by the white blood-corpuscles of wandering 

 outside of the vessels was discovered, and also their power 

 of removing substances deleterious to the system, bacteria 

 amongst others. In order, therefore, to be able to follow up 

 the fate of bacteria which find their way into the body, or the 

 fate of the body into which bacteria have been introduced, 

 it will be necessary to direct our attention for a moment to 

 some of the phenomena of inflammation. For our present 

 purpose it will be sufficient to consider the blood, the irritated 

 part, and the blood-vessels in its vicinity. The blood consists 

 of water holding in solution albumen, fibrin, and various salts, 

 with an infinite number of minute cells suspended or floating 

 throughout it. These cells are the red and the white cor- 

 puscles. With the red blood-corpuscles we have nothing to 

 do for the moment. It is the white corpuscles, or leucocytes, 

 which claim our attention. The white corpuscles are soft- 

 bodied globular cells about T^^-g^jfjin. in diameter, composed of 

 protoplasm, and possessing a nucleus or nuclei and nucleoli. 

 Sometimes vacuoles are seen in their interior. They have 

 been aptly likened to the x\moeba. The Amoeba is the simplest 

 form amongst the protozoa. It consists of a minute mass of 

 jelly, a simple cell without organs — unless the nucleus be 

 an organ, or the vacuoles wdrich may appear at any time. It 

 possesses the power of movement by shooting out portions of 

 its protoplasm, which serve as arms or feet (pseudopodia). It 

 nourishes itself by investing any small body capable of 

 affording it nutriment with its protoplasmic substance, sur- 

 rounding the morsel with its body. It can reject any in- 

 nutritious or noxious particle wdrich it may have enclosed, by 

 simply withdrawing its body from the particle, and leaving it 

 outside. 



The analogy between the Amoeba and the white blood- 

 corpuscle, or leucocyte, seems complete. The leucocytes are 

 little particles of protoplasm, monocellular, and nucleated, and 

 sometimes vacuolated. They are endowed with the power of 

 movement by means of little feet-like processes which can be 

 shot out and again retracted. They can take particles of 

 foreign matter into their interior and digest them or reject 

 them, just as the Amoeba can do. We have thus living in our 

 blood little cells possessing a life of their own, having the 

 faculty of movement with which our will has nothing to do, 

 of selecting and digesting food, and, as we shall see after- 

 wards, the power of avoiding some matters which would act 

 as poison to them. 



And now a few w^ords with regard to inflammation. The 

 definition of Celsus as to the external characteristics of in- 

 flammation reigns to this day in our text-books — namely, 

 "redness and swelling, with heat and pain" — " Eubor et 



