132 Proceedings of Royal Society of Edinburgh. [sess. 
seventh and eighth, which set forth the same for the uninoculated, 
one gets a good idea of what would happen in a plague-stricken 
place if all the inhabitants were to he inoculated. For if the 
uninoculated half of the villagers had also been operated on — and 
there would not have been the slightest difficulty in doing this — 
the mortality among them would have been reduced 89*6 per cent, 
from what it actually was, or, in other words, they would have had 
ten times fewer deaths. For if the inoculated had suffered to the 
same extent as their uninoculated relatives, they should have had 
29 deaths from plague, instead of 3 only. The proportional 
number — 2 9 ‘—is reduced by 26, which is equal to a diminution of 
89 - 6 per cent, of mortality attributable to inoculation. 
As throwing light on the time necessary for the prophylactic to 
act, the subjoined figures, showing the number of days which 
elapsed between the date of inoculation and the occurrence of a 
death from plague in those families is instructive. The small 
figures show the number of deaths on any one day. 
In the inoculated, deaths took place — 
------- - 91- -121-141- - - - - ___ 
and in the uninoculated, deaths took place — 
_ _ 32 41 53 _ 72 - 103 113 121 - - 151 161 - - 191 201 211 - - 
241 ------- 321 - _ - - - - - - - 421 days 
after date of inoculation. 
Eight days, therefore, elapsed after operation before any deaths 
occurred among the inoculated, while during this time 11 deaths 
from plague were registered among the unprotected. It would 
seem, then, that the inoculation acted at once, and, as will appear 
later, this is borne out by many other observations. 
The following table shows the occurrences in the twenty-eight 
affected households, arranged according to sexes : — 
Inoculated. 
Not Inoculated. 
Numbers. 
Oases. 
Deaths. 
Numbers. 
Cases. 
Deaths. 
Males, 
41' 
4 
3 
24 
7 
7 
Females, 
30 
4 
40 
20 
19 
Total, . 
n 
8 
3 
64 
27 
26 
