224
THE VANGE MINERAL WATER.
By JOHN C. THRESH, M.D., D.Sc., Etc.
THE mineral water which has recently sprung into notoriety
escaped the attention of the writers when preparing the
Geological Survey Memoir on the water supply of Essex. Some
20 years ago, Mr. E. Cash, having purchased the Vange Hall
Estate, which is all on the London Clay, noticed that at one spot
the ground was always moist. He collected a little of the water,
and finding that it had a saline flavour he submitted it to Dr.
Rideal for analysis. So much sulphate of magnesium, sodium
and potassium was found in it that Dr. Rideal pronounced it a
medicinal water, and Mr. Cash's experiments upon himself
and friends led him to think these properties were very valuable
indeed ; in 1922, some almost miraculous cures being reported,
certain gentlemen connected with the London Press began to
enquire into it, and in consequence of their investigations the
publicity given to the water caused an extraordinary demand.
The writer went over and obtained a sample of the water and
Mr. Cash, junior, courteously shewed him the well from which the
water is raised to the pump-room. It is in a shallow valley
running nearly north and south down the side of the hill to the
north of the main road near Vange Church.
The subsoil here is a heavy loam and yields a little water.
Samples have been collected from the wells around, varying
it is said from 14 to 60 feet in depth, and all yield sulphated
waters. Some, however, have been abandoned, and surface-
water gains access. Consequently they are more or less polluted
and the true loam-water diluted. Mr. Cash, however, is con-
structing his wells so as to prevent the influx of surface-water,
and there is no other possible source of pollution near the site.
The loam or clay here is rich in crystals of selenite, and in fissures
in the clay and in the masses of Septaria layers of crystals of
calcium sulphate abound. In the neighbourhood of the wells
the clay, thrown out in excavating, dries and becomes covered
with a white efforescence, which dissolves in water and consists
chiefly of calcium and magnesium sulphates.
Sulphated waters are common in Essex throughout the
whole London Clay area. They all contain calcium and mag-
nesium sulphates, but comparatively few contain also the cor-