268 How, When , and Where is Sewage Injurious ? [May, 
discomfort to persons living near, — if it offends their senses 
of sight or smell, — the public have surely a full and indis- 
putable right to complain, and to demand the legislative 
suppression of the mischief. My definition of “ nuisance ” 
is therefore wider than that too often accepted. I should 
include under the term any matter, whether solid, liquid, or 
gaseous, which is in itself injurious to health, or which may 
become so in contact with other substances, whether the 
latter be in themselves hurtful or not; further, any matter 
which — though not demonstrably poisonous or hurtful — is 
offensive to the senses. 
There are, of course, certain limitations to be kept in 
view. Solid, non-volatile matter on private premises cannot 
be regarded as a nuisance as long as it can neither contami- 
nate the air nor be washed into rivers and water-courses, or 
out on to public roads or the land of other persons. 
Sewage contains, or rather consists of, to a great degree, 
liquid or at least soluble matter, and, being liable to rapid 
chemical changes, it gives off volatile products — gases and 
vapours — in abundance. These gases and vapours are 
highly offensive to the sense of smell, and if not direCtly 
poisonous, as is still often maintained, they lower the vital 
tone of persons who habitually respire air with which they 
are mixed. The real danger of sewage, and of water to 
which it has been added, is that it often — if not always — 
contains minute living organisms, bacilli, &c., some of which 
are found to be causally connected with infectious diseases. 
These tiny organisms, named collectively “ microbia,” are 
apt to increase and multiply in the water of rivers, wells, or 
pools into which sewage finds its way. The water is thus 
rendered unfit for consumption by human beings, or even by 
cattle. It may produce sickness and death even if used, 
e.g., for rinsing out milk-pails, washing cooking-utensils, &c. 
It may be urged in opposition that there are places, many 
of which I know, where the only water available for do- 
mestic consumption is drawn from shallow wells, separated 
from cesspools by a few yards of chalk, gravel, or other 
porous subsoil ; yet* the general standard of health in the 
district remains good. 
To this I reply that the residents of such neighbourhoods 
have, by a process of “ natural selection,” become inured to 
the effects of polluted waters, whilst a stranger coming to 
live in such localities is often seriously affeCted. But, above 
all, the health of a population using polluted waters depends 
on what is commonly called accident. If a single case of 
typhoid fever, dysentery, or cholera is introduced into such 
