XVIIL] NON-PATHOGENIC ORGANISMS. 241 



constant symptom of the disorder ; in such necrotic patches 

 the capillary blood-vessels are sometimes, not always, found 

 distended and plugged with the zooglcea of putrefactive 

 micrococci, which have nothing to do, specifically, with the 

 real disease (see a former chapter). 



The cavity of the alimentary canal, small and large 

 intestine, especially the latter, contains under normal con- 

 ditions innumerable masses of putrefactive micro-organisms. 

 These being much smaller than chyle-globules, must of 

 necessity become as easily absorbed as the latter by the 

 lacteals, and by these are carried into the general circulation ; 

 but being putrefactive they are unable to resist the action of 

 the normal blood, and therefore in the healthy condition 

 perish. But if there be in any part a focus of disorganisation 

 they can settle there and propagate, provided they get there 

 through the blood in a living condition. Many experiments 

 prove that they cannot pass unscathed through the normal 

 healthy blood, and therefore it is not probable that they 

 would reach such a focus in a living state ; but let them be 

 well inclosed in a solid particle, say of disorganised tissue, 

 and then carried through the vascular system, and we can 

 quite understand that in this state, i.e. in and with that 

 particle, they may reach the distant focus in a living state, 

 and if in this focus the conditions are favourable for their 

 growth, e.g. if there is inflammation and necrosis, we may 

 expect them to multiply accordingly. 



It is now admitted by most competent observers that in 

 the healthy and normal state the blood and tissues contain 

 no micro-organisms whatever, and that the assertions to the 

 contrary are due to errors in the experiment, i.e. to accidental 

 contamination. I will on this point merely refer, amongst 

 many others, to the observations of Watson Cheyne l and 

 1 Pathological Transactions, vol. xxx. 



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