THE CHALK WATER SUPPLY OF YORKSHIRE. 31 
My lecture was brought to a conclusion by giving the analyses 
of various Yorkshire waters taken from Mr. Thomas Fairley’s 
pamphlet on the subject,* and by contrasting the water in the 
chalk here with that obtained from the chalk at Dover, the total 
amount of dissolved solids, viz., about 203 grains per gallon, being 
practically identical in both samples. 
* “The Water Supply of Yorkshire.” Journal Federated Institutes of 
Brewing. Vol. iv., No. 5, May, 1898, pp. 393-495: 
THE CHALK WATER SUPPLY OF YORKSHIRE. 
By JoHN ROBERT MortTIMER.* 
HE drift clays and superficial deposits of Holderness cover 
the chalk in a wedge-shaped mass, the thin edge of which 
fringes everywhere the inner margin of the gradually out-cropping 
chalk wolds at elevations varying from 60 to 100 feet above 
sea level. Their thick sides adjoin the sea and the Humber, and 
have a depth of from 50 to 200 feet, the upper portion of which, 
between Bridlington and Spurn, forms the cliffs, whilst the 
lower beds extend under the ocean. 
Immediately underlying the quaternary deposits is the chalk, 
which, in the neighbourhood of Hornsea is roo to 130 feet below 
sea level. From here the chalk rises northwards and westwards, 
and comes to the surface in a zigzag line. This mass is 
wedge-shaped, and lies with its thick side to the East. At 
Hornsea it is 800 feet in thickness, and at its northern and 
western terminations 300 to 500 feet. 
Under the chalk lie the impermeable Kimmeridge and 
Neocomian clays, at Hornsea about gro feet below the level 
of the sea. They also rise northwards and westwards, and 
at their outcrop, along the base of the outer margin of the 
chalk, rise to an elevation of from 100 to 600 feet. The upper 
side of these impervious clays forms a basin, in which in the 
main rest the chalk and the drift clays of Holderness. Their 
thickness, though considerable, is unknown. At Malton the 
Kimmeridge clay was bored to a depth of 460 feet, and at Norton 
Villa to nearly the same depth, without passing through it. 
The chalk of Yorkshire is a most important water-bearing rock, 
* Reprinted (with slight alterations) from vol. lv., of the Proceedings of the 
Institute of Civil Engineers, by permission of the council of the Institute, and 
of the author. 
