THE VANGE MINERAL WATER. 225 
responding sodium and potassium salts. They are found both 
near the surface and throughout the clay to its base. The deep 
wells or bores are nearly all abandoned, but some are still to be 
found about Mundon, Althorne, Stow Maries, and Bulphan. 
At the last named place the water contains also a considerable 
amount of common salt. 
Two wells may be sunk in the same parish, yet the waters 
be markedly different. A single example will suffice. In the 
parish of Althorne are two wells about a mile apart. In both the 
water is derived from the basement-bed of the London Clay 
which formation here is about 300 feet thick. These waters 
were both sulphated, but differed considerably, as the following 
analyses show :— 
Parts per 100,000. 
No. 1 well No. 2 well. 
MoG@mantacnonate. ... 23.0 ~~ .sseuaee 201.3 
eeeempnatcs .. 92.0  -s.t.e.. 7S, 
Meewetimestiphate .. -120.0, ........ 42.5 
Sodium sulphate a OS® Wi! 2mm. 59.2 
Sodium chloride eee Os Le ints tS 49-3 
Silica, &c. a ee SEO ae eee paca 
Total solids Ra O Me ig tera. cis 190.0 
Within a mile the same stratum yields a water which contains 
no trace of calcium or magnesium sulphates and comparatively 
small quantities of sodium sulphate. 
A bored well near Wick House, on Bulphan Fen, gave the 
following results—in parts per 100,000. 
Calcium carbonate oe oh 29.3 
Calcium sulphate a ue II4.9 
Magnesium sulphate ie Le 362.5 
Magnesium chloride ae a 45-5 
Soqium) Giloride  .. te: a3 231.0 
Water of hydration, etc. .. Age 34.8 
Total solids ae 818.0 
These deep well-waters have never been used medicinally, 
but in past times sha!low well-waters, rich in sulphates, have 
acquired a reputation, notably at South Weald, Upminster, and 
Hockley. The following analyses of these waters are taken 
