140 RESPONSES OF CELLS ON THE BIOLOGICAL LEVEL 



within a few hours. But when a very small dose of lewi- 

 site is applied to the skin, there is a transient effect which 

 passes off after about two hours, and may be followed 

 several days later by a much more profound effect which 

 may result in the death of cells after about a week (Fig. 

 21). It is very probable indeed that the destruction of 



* Large rfose 

 '^ Small dose 



/ 



Compjeie stoppage 

 of circulation 

 \Many clots in 'arger 

 vessels 

 ISome clots in larger 

 ivessels 



} Massive diapedesis 

 .red cells 

 L J ] Slight diapedesis 



I I \red cells 



I * / • ^Stasis in capillaries 



.^.^, / ^Dilatation of larger 



\vessels 



J Gross Capillary 

 dilatation 



\ -^ -Capillary dilatation 

 Xj-x '£— I I Normal 



0.1 0.5 10 5 10 50 100 200 



Hours 



Fig. 21. The response of the skin of the ear of rabbits to large and 



small doses of lewisite 



cells caused by relatively large doses of lewisite, and the 

 transient interference with cellular activity observed 

 soon after slight contamination, can be attributed to 

 cytoplasmic damage. But whether the secondary phe- 

 nomena developing with slight contamination are due to 

 cytoplasmic or nuclear damage is much more difficult 

 to decide. The secondary phenomena are probably closely 

 related to systemic poisoning by arsenical compounds, 

 so that the solving of this problem is not necessarily of 

 academic interest only. 



