466 BIOLOGICAL PHYSICS 



lymphatic, but that it does not enter into the causation, or 

 regulation, of the phenomena in question, its presence only 

 becoming known in connection with certain pathological 

 conditions in particular. 



These vasculatures, being the capillary blood-vessels, and 

 the nerve terminals of the skin, and, consequently, circu- 

 lating blood and cerebro-spinal fluid plus neural plasma, 

 respectively, necessarily colour the skin through which they 

 are conveying their contents, strictly in accordance with the 

 proportions in which, for the time being, the two fluids are 

 circulating. Thus, for example, under the stress of severe 

 or sustained bodily exercise, it will be found that the blood 

 contents of the capillary vessels, continuously pumped 

 hither, at last superabound and overshadow those of the 

 nerve terminal vasculature ; hence the flushing, hence, also, 

 the blushing of shame or remorse, when the heart, violently 

 agitated, projects its contents into these tell-tale regions, 

 and measures out, with more or less fidelity, its depth and 

 character ; hence, also, the blush which mantles the " cheek 

 of innocence," through the influence, it may be, only or 

 merely of a " shade of thought," and the quick response of 

 a cardiac organism attuned to neural impulses and cerebro- 

 cardiac sympathies. Thus also, under the influence of 

 shock, fear, or " intense feeling " of various kinds, we may 

 witness the counterpart to these haemal displays in the 

 temporary, and, alas ! sometimes the permanent, arrest and 

 withdrawal of the circulating blood from the blanching 

 cheek, and the intensification of the natural pallor by 

 stronger and fuller invasion of the neuro-terminal vascula- 

 ture by the pale and colourless elements of the cerebro- 

 spinal lymph streams and the pearly nerve plasm, with the 

 final disappearance of every vestige of colour, as the pall of 

 unconsciousness falls over the thousand-fold activities of 

 the sensorium, and "life in death, "or death itself completes 

 the scene. 



In trying to appreciate the phenomena of the flush, the 

 blush, and the blanch, we must bear in mind that in doing 

 so we are looking upon a histological collection of micro- 

 scopic vessels of varying lumen, conveying differently 

 coloured and shaded fluids, actuated by a dynamic organ- 

 ism, sensitive to the slightest influence flowing from its 



