t 4S ] 
1904. 
Rainfall. 
Total 
Cases. 
Deaths. 
1st. 
Attacks 
only. 
June 
3.80 
2 
• • 
I 
S.W. Monsoon. 
July 
7.88 
6 
3 
August 
4.10 
2 
• • 
Sept. 
1 
• • 
N.E. Monsoon. 
The exclusion of cases admitted with the disease is made as the gaol 
conditions cannot be held responsible. Prisoners awaiting trial have not 
the same medical examination and are under different conditions so these 
also are excluded. In the tables published by Travers these classes of 
cases are included. 
The average gaol strength is about 500, so that the incidence of the 
disease was not extraordinarily heavy. 
There is also reason to believe that some of these cases were infected 
previous to their term of imprisonment. Of the 8 fresh cases one developed 
the disease within a week of admission and 3 under 2 months. Some at 
least of these may have been infected before admission. Of the other four 
cases one had been 7 months in gaol, 2 10 months and one a year. These, 
I consider, prove that the source of infection still exists, or is, from time to 
time, introduced amongst the prisoners, and that the conditions necessary for 
the spread of the disease still exist to a minor extent. Between November 1st, 
1903, and September 30th, 1904, there were 9 cases admitted with the disease 
not included in the above lists. Three of these were admitted in November. 
No prisoners were admitted into the gaol in the previous 8 months with the 
disease. The cases occurring in the gaol before this date were both under 
two months after admission. The first cases which occurred (3), 7 months 
or more after imprisonment were in the following March, and in that month 
also two persons were admitted with the disease. 
It has, I consider, been proved that the period of incubation of the 
disease is variable, and also that it may be short, but it has not been proved 
that it may not be as long as two months or even longer. It would appear 
probable that the source of the outbreak is to be found in the admission of 
prisoners in the incubation period and its continuance to the introduction 
by them of the disease into the goal. 
A similar sequence of events occurred in the Singapore gaol at the 
commencement of the outbreak there in September, 1903. There had been 
no fresh cases for over 3 months, but one occurred in September in a prisoner 
5 weeks after admission. In October there were two cases in short 
sentence prisoners, but one of these had been over 3 months in gaol. In 
November there were 32, including 6 who had been over a year in the gaol, 
and in December the epidemic reached its maximum of 41 cases, including 
5 who had been in gaol over a year. 
1 he incidence of the disease in the first 3 months of the epidemic was 
heaviest amongst the short sentence prisoners, 64 cases, and amongst the 
lower grade prisoners in the first year 13. The average strength of these 
