OF THE BLOOD AXD CIKCULATIOX. 



211 



[374. A magnifying power of from two to three hundred 

 diameters is required, to make out the particular details of the 

 peripheral circulation. The blood in mass, or in the larger 

 channels, is seen to flow more rapidly than in the smaller. 

 Here the blood-corpuscles advance with great rapidity, espe- 

 cially in the arteries, and with a whirling motion, and 'form a 

 closely crowded stream in the middle of the vessel, without 

 ever touching its parietes. 

 With a little attention a 

 narrower and clearer but 

 always very distinct space 

 is seen to remain betwixt 



.1 



the great middle current 

 of blood-corpuscles and 

 the bounding walls of the 

 vessel, in which a few of 

 the lymph-corpuscles are 

 moved onwards, but at a 

 vastly slowerrate (figs. 22$ 

 and229,#,). Theseround 

 lymph-corpuscles swim in 

 smaller numbers in the 

 transparent liquor san- 

 guinis, and glide slowly, 



and in general smoothly, Fig. 228. A venous branch from the 

 though sometimes they ad- web of Ran, temporana magnified 350 

 vance bv fits and starts times, nmning immediately under the siir- 

 ". -! i .-, lace. The cells of the epidermis, o. o. o, o, 



more rapidly, but with in- flattened> mostly sh j sille( i, connected 



tervemng pauses, and, as a Hk e a piece of pavement, and generally 



general rule, at least from provided with nuclei, are seen extended 



ten to twelve times more over the vessel. The closely serried co- 



slowlvthan the corpuscles luran of Wood-globules, some with their 



c , i ' i mu edges, others with their broad faces 



of the central stream The tunipd to the eve> is dlsti%mished . in 



clear space filled with li- the clear space betwixt the blood-globules 



quor sanguinisand lymph- and the parietes of the vessel, which ap- 



corpuscles is obvious in all pear made up of longitudinally disposed 



the larger capillary vessels, parallel fibres, the round, clear, and more 



whether artpvifll nr venous slu gg lishl >' moving lymph-globules are ap- 

 parent. The object is represented under 



but it ceases to be apparent a -weak light. 



hi the smaller intermediate 



vessels, which admit but one or two ranks of blood-corpuscles 



P2 



