| Water is the substance of life. It can also terminate human life if
the life it supports causes diseases such as cholera or typhus. Up to
and including the middle of the 19th century sources of drinking water
included distilled water, rainwater, well water, mineral springs, lakes,
streams and rivers. It would have been unfortunate for the 18th or 19th
century apothecary, chemist and druggist or pharmacist if the water he
used was killing off his clientele.
Physicians would sometimes write
in their prescriptions the type of water that they required to be used.
The two most common were aqua fontana (spring water) or aqua destillata
(distilled water), but others included aqua communis (common or plain
water), aqua puteana (well water) and aqua pura (filtered water).
Moreover,
some physicians prescribed pills or powders with instructions to the
patient to take them with “small beer”, a weak beer resulting
from a second fermentation of the beer mash. This was slightly safer
(and, perhaps, more palatable) than drinking water because the water
used had been boiled before the brewing process. The source
According to Pereira’s ‘Materia medica’ (1854), “besides
rainwater some spring, well, and river waters are remarkable for their
purity. The water of the Malvern springs is remarkable for its extreme
purity. According to Sir Charles Scudamore’s analysis this water
contains only about a third part of the solid matter found by Mr
R. Phillips in Thames water taken at Chelsea.”
Pereira makes further comments about various waters. He noted that the
purer the water the more it would be contaminated with lead from storage
vessels and water pipes. Distilled water, however, had no action on lead
provided air had been excluded. In addition, mineral water appeared to
have a “protective action” against lead poisoning that varied
according to its contents.
However, it was not until 1885 that the British Pharmacopoeia stated: “In
dispensing prescriptions, aqua should be understood to mean distilled
water.” Aqua fontana was not to be used unless specifically ordered.
For official preparations it said: “Natural water, the purest that
can be obtained, cleared, if necessary by filtration; free from odour,
unusual taste, and visible impurity. To be used whenever ‘Water’ is
ordered in the British Pharmacopoeia.” The monograph on distilled
water describes its preparation as:
Take of Water 10 gallons
Distil from a copper still, connected with a block-tin worm; reject the
first half-gallon, and preserve the next 8 gallons.
In “The art of dispensing” (1895) it is suggested that the
water should be boiled before use to drive off any absorbed carbon dioxide
which might precipitate salts from medicinal ingredients. The water should
be freshly prepared and each 5 gallons (22L) should have 10 grains (600mg)
of potassium permanganate and 1 drachm (3.5ml) of sulphuric acid added
to destroy any organic matter that might contaminate it.
According to Pereira, rainwater was suspect. It was not too pure in industrial
towns — having passed through heavily polluted atmosphere — and
could easily be contaminated with lead via gutters, gulleys and drainpipes.
Collection of rainwater for dispensing should be collected at a distance
from the town. Melted snow from the countryside was acceptable.
Well water was similar to spring or mineral water. It was recommended
that the well should be at least 20m deep, have an impervious lining
and was not situated less than 100m from a cesspool. It also required
a well-sealed cover on a raised brick wall and a pump — a bucket
on a rope is a romantic image but was an easy source of contamination
unless kept scrupulously clean.
For Pereira, water hardness was another consideration. He states that
hard water is a “less perfect solvent of organic matter than soft
water; hence, in the preparation of infusions and decoctions, and for
many economical purposes, as for tea-making and brewing, it is inferior
to soft water; and, for the same reason, it is improper as a drink in
dyspeptic affections.
Moreover, it proves injurious in urinary deposits.
The unfavourable effects of hard waters are especially manifested in
horses.”
The problem with lakes, streams and rivers was that, although they might
have appeared clear and pure, they were often used as open sewers for
villages, towns and cities. Despite this, the River Thames, containing Vibrio cholerae and Salmonella typhi,
was London’s
main source of drinking water.
According to “Table traits, with
something on them” by John Doran (1854), water from the Thames
was “offensive
to the sight, disgusting to the imagination and destructive to the health”.
Pereira states: “Thames water, when taken to sea in casks, soon
becomes putrid and offensive, and evolves inflammable vapour.” This
was due to gases formed from organic material decomposing.
Filters
Museum of the Royal Pharmaceutical Society
Doulton household water filter, c1885 |
 |
Perhaps the greatest innovation in the 19th century for the production
of water suitable for drinking and for the manufacture
of official pharmaceutical preparations was the development of water
filters. It is believed that as early as 1827, Henry Doulton was working
on the development of ceramic filters which would remove bacteria from
drinking water.
Traditionally, filters for water were composed of layers
of substances such as sponge, gravel and charcoal. These filters could
not be cleaned and had to be renewed. Doulton’s filters were made
from various earth and clay materials and could be scrubbed clean and
re-used. Queen Victoria was impressed and, in 1835, commissioned Doulton
to produce a water filter for the Royal household.
In 1862, Doulton introduced
a manganous carbon filter and was able to manufacture filtering apparatus
for commercial and domestic use, many of which were highly decorated.
The next development by Doulton was in the use of diatomaceous earth,
also known as kieselguhr, to produce ceramic filters. This is a naturally
occurring, soft, chalk-like sedimentary rock that is easily crumbled
into a fine white or off-white powder and has a high silica content.
It is composed of the shells of diatoms — pre-historic, algae-like
creatures.
Dampened and fired it produces a filter capable of removing
99 per cent of water-borne bacteria. The filters were cast in the shape
of candles with a hollow centre closed at one end and these were enclosed
in a lidded vessel. Water permeates through the filter and is carried
off through the empty centre of the candle. This principle is still in
use today in industrial filtration.
In 1901 Doulton was knighted and in 1902 he was conferred the royal warrant
and the right to use “royal” in front of his company’s
name for his work on drinking water filtration. However, Doulton was
not the only manufacturer of filters. Operating in the second half of
the 19th century was the Silicated Carbon Filter Company in Battersea,
London.
The company manufactured filters which, in an advertisement in Chemist
and Druggist, it describes as “the most effective means known
of purifying water for domestic, manufacturing and general purposes”.
Its range included pocket-sized filters for travellers and it published
an analysis of the effect of the silicated carbon filter upon Thames
water obtained near Battersea Bridge at high water (see Panel below).
Effect of the silicated carbon
filter
|
Unfiltered |
Filtered |
Total solid contents of an
imperial gallon (about 4.5L) |
33.5 grains (2.2g) |
8.7 grains
(0.6g) |
Hardness, as determined by
Clark’s test |
13 degrees |
6 degrees |
Earthy carbonates deposited
by boiling one gallon |
11 grains |
None |
Organic matter contained in
an imperial gallon |
3.8 grains (0.2g) |
0.6 grains (39mg) |
|
In Chemist
and Druggist, of 14 March, 1868, the company had announced : The filtering media employed in the manufacture of these Patent Filters
consist of an intimate combination of carbon, in its most effective form,
with minutely divided silica, as these substances exist in the celebrated
Torbane Hill mineral; and it has been satisfactorally demonstrated that
this compound, prepared under the patent process, is immensley MORE EFFECTIVE
in the purification of water than carbon, both as an oxidiser and as
a promoter of chemical combination generally.
It also claimed the advantages of its filters included that:
• They removed all colour, taste, and odour arising from the decomposition
of organic matter, and rendered the most noxious gases harmless
• They entirely removed the poisonous salts of lead and other bases even
when in solution
• They imparted freshness to flat water
• They had purifying properties, which were “unerring and continue
undiminished”
• The filtered water has no tendency to produce animal or vegetable organisms
• They materially reduced water hardness
• They were free from derangement, and general economy “as experience
has satisfactorily proved that they do not become softened by continued
use like moulded charcoal”
• No water could pass except through the silicated carbon because as
it was securely held in the filtering vessels by “a pure, impervious,
and insoluble cement”, while with other filters where tubes or
corks were used, much of the unfiltered water passed “by capillary
means between the tubes or corks and the carbon”
And lastly:
Because, with the sole exception of salt water, there is none they do
not render SPARKLING, WHOLESOME, and AGREEABLE.
J. H. Graham & Co of 25 Finsbury Place, London, produced carbon
block filters for household and bedroom use which “received high
commendation from medical authorities”. The Berkefeld Company in
Germany were producing ceramic filters in 1891. They had an office at
121 Oxford Street, London. In 1985, Doulton acquired the rights to the
Berkefeld trademark, later changed to British Berkefeld.
Advertisement for the Mawson filter in Chemist & Druggist Diary;
1895 |
The Mawson Filter
Co, 137a Pilgrim Street, Newcastle-on-Tyne, produced gravitational filters
adapted for “Dwelling-houses, Schools, Hospitals,
Soda-water Factories, etc., giving a continuous supply of pure water
without attention … Perfected with the aid of exact analysis, tested
by experts and Medical Officers of Health, and adopted after rigid trial
by the highest authorities in Sanitation in the world.”
The main problem with filters is that they need cleaning. Deposits would
build up and it was possible for bacteria to grow on this deposit or
even through the filter. Cleaning with a brush was recommended every
three days. This period was extended in the 20th century by impregnating
the outside of the filter with silver which renders bacteria unable to
reproduce. The ceramic candle-type of filter is still used today and
they can be scrubbed up to 100 times.
By the 1930s Britain’s tap water was regarded as safe to drink,
although it was not always suitable for dispensing. In 1955, the BP Addendum
introduced purified water, which was produced by distillation or treatment
with ion-exchange resins. This was water of BP standard and from then
on, had to be used where “distilled water” appeared in a
formula.
|
The
Pharmaceutical Journal