28 HISTORY OF COLCHESTER CORPORATION WATER WORKS 
Analyses of Chalk-water are given in the Appendix to this 
paper. 
From personal observations, my impression is that the Chalk 
discharges freely into the river Stour in the neighbourhood of 
Sudbury. There might, however, be times when the river is 
discharging into the chalk at periods of low rain-fall, and these 
are matters which local geologists might set themselves to deter¬ 
mine. No. i is an analysis of the chalk water by Dr. Foster, 
M.A., F.C.S., from the new well, before it was reconstructed in 
1889. No. 2 is an analysis of water from the same source in 
1894, by Mr. W. Chattaway, Analyst to the Borough, after the 
reconstruction of the well, and No. 2 a from the same source by 
Dr. Thresh, M.D., D.Sc., in 1898. 
It should, however, be noted, when there is water to spare 
from the Lexden springs, or when the engine which pumps that 
water is not at work, it is run into the well in order to assist the 
underground source; this may have some slight effect on the 
chemical constituents of the pure chalk water when analyses are 
taken in the future. No 3 is an analysis of the chalk water from 
the Sudbury Corporation Water Works well, and No. 4 is an 
analysis of chalk water from Halstead Urban District Council well 
Comparing the analyses of the chalk water at .Sudbury 
and Halstead with Colchester, about twelve miles apart, it will 
be observed that the water at Sudbury and Halstead is tpyieal 
hard chalk water with 21-5 and 18 degrees of hardness respectively 
and only 3-18 and 4-2 grains of chlorine per gallon, whereas at 
Colchester the chalk water is comparatively soft, and contains 
about 10 degrees of hardness, but has from 21 to 22 grains of 
chlorine per gallon ; otherwise the chemical characteristics of the 
Colchester water compares with the deep well water common to 
this part of Essex, and which have been so exhaustively treated 
and recorded in the Club’s transactions by Dr. Thresh. The 
chief characteristic of the Colchester well water is the chlorine 
in the chalk, but, that has been practically constant to my know¬ 
ledge for the last 23 years. As to the origin of the chlorine, I 
believe no definite decision has been arrived at, but as we 
approach the coast in certain directions it goes up by leaps and 
bounds. To my mind the only rational conclusion one can come 
to to account for it is the process of diffusion through ages of 
time. 
