1884.] The Ghost of the Season. 263 
kept back from entering the streams along with the effluent, 
or, if not kept back, can they be destroyed by oxidation or 
by any other process ? Professor Frankland seems to have 
attended and testified that these “ germs ” — like nuisances 
generally — are very tenacious of life. He told his hearers 
that they might be boiled for three or four hours without 
being destroyed, and that they were little affedted by cyano- 
gen and sulphurous acid. Dr. Jabez Hogg, the eminent 
microscopist, also declared that oxidation in the flow of a 
river could have little effedt upon living organisms, however 
efficient it might be in the removal of dead organic matter. 
All this may, for argument’s sake, be very well admitted, 
though it is important to note — as Sir Robert Rawlinson 
pointed out — that cholera can at all events originate on a 
very large scale independently of germ-polluted waters, 
whilst that disease may rage in one town, and another town 
situate lower down the same stream, and using the contami- 
nated waters for domestic purposes, may entirely escape. 
Cholera has also not unfrequently been known to work up a 
river, instead of following the current. Such fadts as these, 
I submit, ought not to be entirely overlooked in speculations 
on the spread of zymotic disease. 
But to return : if disease-germs, when once in a river, 
cannot be destroyed, the question remains whether such 
germs, if present in sewage, can by any mode of treatment 
be kept back. Dr. P. Frankland made the honest admission 
that “ there is absolutely no evidence that morbific matter, 
if present, would be removed ” either by irrigation or 
“ downward intermittent filtration.” He even stated that, 
“ On the contrary, there is very strong reason to believe that 
these processes of purification offer no sort of guarantee 
that noxious organised matters present in the sewage may 
not pass through into the effluent. For the removal of 
organic matter by means either of irrigation or intermittent 
filtration depends upon the oxidising afflion which a porous 
soil exerts upon such matter, and is quite analogous to the 
purification of water percolating through a few feet of soil 
into shallow wells. Now, the instances on record of the 
percolation of sewage into shallow wells becoming the means 
of infedtion are so numerous and well authenticated that it 
is unnecessary for me to refer to them here. ... At Stutt- 
gart in Germany, and Winterthur in Switzerland, some 
years ago, epidemics of typhoid fever were proved most 
conclusively to have been caused by the contamination of 
the water-supply with the effluent from irrigated meadows.” 
Dr. Jabez Hogg cited the well-known case of a stream in 
