44 THE ESSEX NATURALIST
but eventually this water was used. The spring water "must be
very pure", he said, "as I am informed that steam engines get out
of order if very pure water is not used". It was this water which
the railway employees drank, as also did coastguard men
stationed in a vessel on the mud bank of the Thames just outside
the Fort. Malaria was unknown among them and the ague was
very uncommon. Therefore, it was argued (mainly from statistics)
that the impure water supply (with an oxidisable organic sub-
stance derived from the marsh through the non-watertight tanks)
was a major factor in the prevalence of these diseases.
That malaria was on the wane in the second half of the 19th
century is evidenced by a number of records in Essex journals.
The reasons given for this are also numerous. Russell, in a note
on 'Ague in Essex' in The Essex Review (1924), recalled, "When I
was a boy quinine was very expensive, and wages were very
small, and so my father kept a supply ready-mixed for free distri-
bution to the ague-stricken; and folk came frequently from both
sides of the river, some from many miles beyond Gravesend.
When my father died in 1887, I found over a gallon of the
quinine; two huge bottles had not been broached. To the best
of my belief there had been no applicants for many years, as ague
had disappeared. The local belief is that it was killed by the
cement works, because the disease died out at the same time the
cement works were started."
In 1888, Dr. Henry Laver (a former President of the Essex
Field Club) read to this Club a paper, based on his own reminis-
cences, entitled, "Fifty years ago in Essex". "Ague", he recorded,
"was once very rife; it has now, in comparison, almost left its old
haunts". He did not consider that this was due to sanitary im-
provements in the way of drainage, felling of timber and so on,
as the decrease of ague had been progressive and began before
the birth of sanitary science. Dr. Laver's explanation was that
germs, like birds and insects, had periods of abundance and then
of rarity. "For some reason", he continued, "which at present is
inexplicable, the germ of ague seems to have worn out its
pabulum and it therefore has become rare. But . . . some day
it will—following a cyclic law—again appear and have its period
of abundance and virulence". Fortunately, such a prophesy has
not come true.
Bacot, Entomologist to the Lister Institute of Preventive
Medicine, presented a paper to this Club in November, 1917, and
in it he referred to a communication from a member, Mr. Thomas
Barrett-Lennard, of Aveley, which recorded, "When I was a boy.
ague was fairly common here. I remember my mother used to
dose workmen on the estate with port and quinine, and she
suffered from it rather badly herself. My father tells me that
when he was young, people used to say, "Have you had your ague
this spring"? This is a phrase often quoted, but I have never
seen its source acknowledged. It is a pleasure to record that it
is, in fact, from our 'Essex Naturalist'. "My grandfather,", con-