102 THE CELL DOCTRINE. 



mass of the blood increases, the proportionate num- 

 ber diminishes with great rapidity. 



Leucocytes, or white blood-globules, are found in 

 many tissues, in the blood, on the surface of mucous 

 membranes ; in a word.they are the pus-corpuscles. In 

 form, they are round, with pale, well-defined bor- 

 ders, and contain extremely fine gray granules. They 

 possess a very thin envelope, and a granular cell con- 

 tents. The normal diameter is .008 millimeter 

 (?T»']nr ^^ ^'^ inch). On the addition of water, the 

 leucocytes swell, the granular particles are agitated 

 by a peculiar movement (first observed by Brown), 

 and finally, a considerable number of these particles 

 unite, so as to form, two or three little masses, that have 

 been mistaken for nuclei. Upon the addition of acetic 

 acid the same reaction follows, but with greater 

 rapidity. 



The mode of production may be followed, step by 

 step, upon the surface of wounds, especially little 

 ones. At first a hyaline liquid appears. At the end 

 of a couple of hours, this liquid becomes finely gran- 

 ular, and then all at once, in the midst of the granu- 

 lations, we perceive small granular bodies analogous 

 to leucocytes, offering the same chemical reactions, 

 but measuring only .003 millimeter (.000118 of an 

 inch) in diameter. They are, in fact, leucocytes of 

 young growth. When leucocytes are retained in the 

 ecbnomy, as in shut sacs, they increase in size, and 

 reach a diameter of .012 millimeter (j^'j^ of an inch). 

 Then they fill with fat-granules, and are known as 

 corpuscles of inflammation (exudation corpuscles, com- 

 pound granule-cells). Finally the substance and in- 



