Diphtheria is probably conveyed and
caused by impure water, but this is not yet
absolutely proved. Dysentery is well known
in tropical countries to be caused by impure
water, as Vv^as proved b}'- an outbreak at Cape
Coast Castle, where it was caused by the
passage of sewage into one of the drinking
tanks. Diarrhoea has been caused in epi-
demic form b}^ impure water, as was shown
in the old Salford jail, where the untrapped
overflow pipe from a cistern of drinking
water communicated with a sewer, and the
water had thus absorbed sewer gas, and
probably germs.
Mineral Impurities. — A moderate de-
gree of hardness is not harmful, but if the
hardness is great dyspepsia and constipation
may result. Goitre seems to be due to the
presence of magnesium limestone in the
drinking water, but this is disputed by some.
Iron salts cause dyspepsia, constipation, and
headache. Lead salts are especially dan-
gerous, causing colic, paralysis, kidney dis-
ease, and sometimes death. These symp-
toms may occur when the amount of lead
does not exceed one-tenth grain per gallon.
Purification of Water.
Fortunately, it is comparatively easy to
destroy the injurious organic impurities of
water and render it wholesome for drinking
purposes. This, it is true, demands
a degree of care and precaution which
many will not take? and as a result of
ignorance and heedlessness, water is
almost ever3^where a common carrier
of disease. The peril of injury from
it can be overcome in a measure by the
11^^ use of domestic filters, composed of
charcoal or other substances. These,
however, are much more effective in
removing the mineral ingredients than
the more dangerous organic particles.
They also are rarely kept pure and
clean, and may become simpl}" breed-
ing places for bacteria.
Boiling. — The only safe way of
purifying questionable water in house-
holds is by boiling. The disease
germs, which can endure unharmed
the low temperature of liquid air, are
destroyed b}^ boiling water. To make sure,
the boiling should be kept up at least
ten minutes. An unpleasant effect of this
is that it gives the water a flat taste from its
loss of air. Some means should be adopted to
restore to it the lost air. This may be done in
a measure by subsequent filtering, the water
slowly trickling down through and absorb-
ing the air.
City Filters. — Of late years many cities
have introduced filters on an extensive scale,
to purify the total supply and thus cut oif
this prolific cause of disease at its source.
The principal means employed for this are
large filter-beds of sand and gravel, though
in some cities spongy iron is used with good
effect. The result has been highly encoura-
ging in the prevention of epidemic diseases,
and filter-beds are likely to be introduced
before many years into the water-supply of
all our larger cities.
Diseases Due to Food,
Food may in various ways give rise to
disease. Overeating is one source of injury
to the system. I^irt of the food is not ab-
sorbed, and may become putrid in the intes-
563
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THE FAMIL Y DOCTOR
Page 245
Presented as published in 1901. Historical recipes may not meet modern food-safety standards. Cook from the modern interpretation, not the original instructions.
AI-modernized reading of the original text
Diphtheria is probably conveyed and caused by impure water, but this is not yet absolutely proved. Dysentery is well known in tropical countries to be caused by impure water, as was proved by an outbreak at Cape Coast Castle, where it was caused by the passage of sewage into one of the drinking tanks. Diarrhoea has been caused in epidemic form by impure water, as was shown in the old Salford jail, where the untrapped overflow pipe from a cistern of drinking water communicated with a sewer, and the water had thus absorbed sewer gas, and probably germs.
Mineral Impurities. — A moderate degree of hardness is not harmful, but if the hardness is great dyspepsia and constipation may result. Goiter seems to be due to the presence of magnesium limestone in the drinking water, but this is disputed by some. Iron salts cause dyspepsia, constipation, and headache. Lead salts are especially dangerous, causing colic, paralysis, kidney disease, and sometimes death. These symptoms may occur when the amount of lead does not exceed one-tenth grain per gallon.
Purification of Water.
Fortunately, it is comparatively easy to destroy the injurious organic impurities of water and render it wholesome for drinking purposes. This, it is true, demands a degree of care and precaution which many will not take? and as a result of ignorance and heedlessness, water is almost everywhere a common carrier of disease. The peril of injury from it can be overcome in a measure by the use of domestic filters, composed of charcoal or other substances. These, however, are much more effective in removing the mineral ingredients than the more dangerous organic particles. They also are rarely kept pure and clean, and may become simply breeding places for bacteria.
Boiling. — The only safe way of purifying questionable water in households is by boiling. The disease germs, which can endure unharmed the low temperature of liquid air, are destroyed by boiling water. To make sure, the boiling should be kept up at least ten minutes. An unpleasant effect of this is that it gives the water a flat taste from its loss of air. Some means should be adopted to restore to it the lost air. This may be done in a measure by subsequent filtering, the water slowly trickling down through and absorbing the air.
City Filters. — Of late years many cities have introduced filters on an extensive scale, to purify the total supply and thus cut off this prolific cause of disease at its source. The principal means employed for this are large filter-beds of sand and gravel, though in some cities spongy iron is used with good effect. The result has been highly encouraging in the prevention of epidemic diseases, and filter-beds are likely to be introduced before many years into the water-supply of all our larger cities.
Diseases Due to Food,
Food may in various ways give rise to disease. Overeating is one source of injury to the system. I^irt of the food is not absorbed, and may become putrid in the intes-
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