94 TRANSACTIONS—PERTHSHIRE SOCIETY OF NATURAL SCIENCE. 
Castle. The one part of the population of these three towns, num¬ 
bering 219,435 got this filtered water pumped up from the Tees, 
whereas the rest of the population num.bering 204,181 received their 
water from other sources than the Tees. Those receiving filtered 
Tees water were in the first six weeks attacked at the rate of 33 per 
10,000, while those receiving other water were attacked at the rate of 
3 per 10,000; in the second six weeks’ period the Tees water gives 
28 per 10,000, as against i per 10,000 in the other case. Had the 
epidemic been one ■ of Asiatic cholera in place of enteric fever, 
Darlinston, Stockton, and Middlesborough, would have undoubtedly 
suffered quite as badly as Hamburg, and here note that the water 
was carefully filtered, and also that these epidemic outbursts occurred 
soon after sudden floods, which washed masses of filth from the 
banks down the stream, and doubtless also hastened the rate of 
filtration through the sand and gravel to such an extent that the 
water was not sufficiently filtered. 
From pages 119 to 124 of this report we have a record of chemical 
analyses during the periods of the outbursts. These analyses are by 
(1) The County Analyst for Darlington. 
(2) Mr. Alfred Allen, Public Analyst, Sheffield. 
(3) Dr. E. Frankland, London. 
In all cases the chemical analyses will compare favourably with 
those of our Perth water. Dr. Frankland reports concerning the 
water drawn during the first six weeks’ period that “The water is free 
from every trace of previous sewage or animal contamination, and the 
microscope reveals nothing of a deleterious character. It is a whole¬ 
some water of moderate hardness, and, with the exception of a peaty 
taste, is in all respects of excellent quality for dietetic and all other 
domestic uses.” 
There are at least five analyses of the filtered water supplied to 
these towns. These analyses extend over a period of three months, 
and in no case was anything discovered to throw any doubt on the 
quality of the water, and yet during these same moiiths the same water 
was carrying disease and death all over the area in which it was being 
used. 
To those interested in this matter, and, I suppose, we all must be 
more or less so, I would most strongly recommend a most careful and 
unbiassed study of Dr. Barry’s report. It proves the fact which I have 
all along contended for in regard to the Perth water supply, that 
water once contaminated with animal excreta is at best a doubtful 
water for domestic and dietetic purposes, whatever results chemical 
analyses may give. Filtering through sand and gravel removes, if 
carefully done, many of the impurities, and may make contaminated 
water as at Altona and Middlesborough, Stockton, and Darlington, 
