View report page

97
Allusion is made to a recent suggestion in reference to poliomyelitis
and its possible association with public bathing, by Dr. Alexander, who
points out " that during July, August and September, when swimmingbaths
are most used, poliomyelitis has its greatest prevalence. He
therefore suggests, as worthy of scientific investigation, that the highly
polluted condition of the baths during those months, and especially the
slime forming on the floor of the baths, possibly provide a factor in the
causation of the disease and a medium of conveyance of the infecting
virus. In support of this suggestion he quotes the reference made by
Dr. Batten in his paper on ' Acute Epidemic Poliomyelitis,' to the
Massachusetts epidemic, in which, out of 150 cases carefully inquired
into, it was noteworthy that 62 were swimming or wading in water more
or less contaminated by sewage before the attack. The point is certainly
one which might well repay careful investigation."
After alluding to various methods of sterilisation or filtration adopted,
Dr. Forbes proceeds to state that " Dr. Alexander has introduced an
entirely different method of sterilisation by the use of electrolytic disinfecting
fluid, a solution containing hypochlorite of magnesia. This
method has been applied for the last three years in the five public baths
in the borough of Poplar.
Briefly, the fluid is prepared by the electrolysis of a saturated
solution of chloride of magnesium (3 tons), together with salt (4½ tons)
and caustic soda, which produces over 27,000 gallons of electrolytic fluid
at a cost of £53, including the amount of electricity used, or at just under
£2 per 1,000 gallons.
The capacity of four of the Poplar swimming-baths varies from
75,000 to 85,000 gallons ; for these an amount of electrolytic fluid of
20 to 30 gallons is added during the filling of the baths. A smaller bath
holding 39,000 gallons receives 10 gallons. Subsequent additions of the
fluid are made at intervals of two or three days, according to the condition
of the water and number of bathers. The bath is emptied and cleansed
at regular intervals of about seven to ten days. The fluid is also used
for cleansing the dressing boxes and side paths of the baths.
The advantages claimed for this method of disinfection are, first:
The water is purified both chemically and bacteriologically by the
oxidising and germicidal properties of the fluid.
Secondly, the water from its purification is far pleasanter to bathe
in, clear and invigorating and free from the usual unpleasant odour.
The cleansing of the bottom and sides is much more easily accomplished,
owing to the absence of slime commonly found at the deep end of the
bath.