MR. K. SUTTOX OX A WELL AT KIRBY BEDOX. 47 
sulphate of lime, or gypsum, seldom more than four or five per cent., 
so that Xorfolk waters will always show the presence of these two 
suhstances. There arc also always traces of iron and alumina from 
days, and of silica from flint or clay, which latter is simply a silicate 
of alumina. The magnesia is derived no doubt from the decom- 
position of minerals existing as silicates of magnesia. The gypsum, 
or sulphate of lime, may either have been derived from similar 
sources, or, more probably, from oxidized sulphur in organic bodies 
or iron pyrites. 
The average composition of waters derived from the Chalk will 
bo as follows ; that is to say, supposing them to bo uncontaminated 
Avith various surface impurities, such a.s sewage or surface 
drainage ; — 
Carbonate of lime, or chalk . . 10 to 15 grains per gallon. 
Carbonate of magnesia . . . 2 „ 3 „ „ 
Sulphate of lime . . . . 3 „ 4 „ „ 
Chloride of sodium, or common salt . 3 „ 4 „ „ 
0.\ide of iron, alumina, and silica . 1 „ 3 „ „ 
Total solid matters varying from . 19 to 29 „ „ 
There arc occasionally to be met Avith, Avaters out of the drift clays 
near the coast, such as Cromer, Yarmouth, Lowestoft, etc., Avhich 
contain larger quantities of these mineral .salts, and especially 
common salt, but it is very rarely that the total solid constituents 
amount to ius much as one hundred grains in the gallon. 
Before describing the details of analysis of this Kirby Avator. 
I Avould just say, that I think it better to simply give the 
constituents in an uncombined state ; and, indeed, this is noAv very 
properly the usual AvaA' of stating the anal3’sis of Avater. Formerh', 
the attempt Avas made to allot the acids and bases according to the 
laAvs of chemical affinity 3 and, in the case of the average Chalk 
Avater giA'en aboA'e, I dare say AA’e cannot go far Avrong in believing 
that the carbonic acid is combined Avitli the lime and magnesia, 
that the sulphuric acid is combined Avith a portion of the lime, and 
that the chlorine is united to the sodium as common salt. But 
Avith the Avater under discussion, the dissolved solids are so 
exceptional in their nature and quantity, that it is difficult to guess 
hoAv they arc combined. 
AVhen first drawn from the avcII the Avater is quite clear, and I 
