78 Researches Regarding Cholera : The Blood. [part i. 



to satisfy ourselves on this point, cursory examinations merely of any number of 

 specimens of blood would have availed but little, consequently the plan already 

 described for the continuous observation of preparations of this nature was adopted. 

 Before starting, however, we satisfied ourselves that the amount of air present in the 

 wax-cells resorted to was amply sufficient by inoculating samples of healthy blood 

 with minute quantities of bacteria ; and observing whether or not the latter could be 

 seen to multiply as rapidly in these closed cells as in similar cells whose walls bad 

 been perforated in two or three places, so as to permit of the free ingress and egress 

 of air, not the slightest difference could be observed. Fungi were also tested in the 

 same way with identical results. Indeed, after the first few hours of observation, 

 many of the preparations here referred to were thus ventilated, but this appeared to 

 have no effect, save to render them more liable to invasion by fungi and acari. 



We have preserved notes of one hundred and twenty-eight specimens of blood 

 derived from various sources, each of which has been kept under observation for 

 periods varying from three days to nearly three months. As, however, these would 

 occupy so much space were they published in detail, we have tabulated the results in 

 as simple a manner as we possibly could. 



It will be seen from the following table that the number of instances in which 

 monads or bacteria appeared in the specimens of blood, whether in health or in 

 cholera, before or after death, is very insignificant ; indeed, in not a single instance is 

 it recorded that any such organisms were present when examined immediately after 

 it was obtained. It may be remarked that no extraordinary precautions were adopted, 

 such as exposing the covering-glass or the needle to the flame of a spirit-lamp — 

 very ordinary precautions indeed having sufficed to prevent contamination to any 

 great extent with any low forms of life whatever. Of the 22 specimens of healthy 

 blood examined, distinct evidence of monads or bacteria was only once observed, and 

 fungal filaments only appeared on three occasions, or at the rate of about 13 per 

 cent. In the blood of cholera patients obtained during life, monads or bacteria were 

 only observed on two occasions in 39 specimens, and fungi were seen to develop 

 in six preparations, just 2 per cent, more than in healthy blood. Except on one 

 occasion, the fungus was observed to have entered the preparation from without, the 

 filaments having insinuated themselves between the covering-glass and the ring of wax 

 at a spot where apposition had not been perfectly effected; in the exceptional case 

 the filament emerged from the clot, and was probably derived from a spore deposited 

 on the covering-glass by the duster. 



The absence of these low forms of life is equally conspicuous in the table of the 

 cholera-blood preparations obtained after death. In the greater part of the specimens 

 so obtained, a series had already been under examination during life. Of the 

 18 cases recorded, there was not a single preparation which manifested distinct 

 evidence of bacteria, either on the first or succeeding days, and fungi developed on 

 four occasions only. 



