ON THE CIRCULATION OF UNDERGROUND WATERS. 353 
In 1866, complying with instructions of ‘the Royal Commission on 
Water Supply,’ of which the Duke of Richmond was chairman, he worked 
out the relation of flood-waters absorbed by the ‘swallow holes’ in the 
basin of the river Colne, and their reappearance as the New River Springs 
in the basin of the Lea. 
In 1880, acting for the united opposition of the London Water Com- 
panies against the Government proposal to buy up the water companies, 
he worked up all that was known as to underground water in the metro- 
politan area. This evidence, unfortunately for our present knowledge, was 
never reached, but its general purport went to show that no large supply 
of underground water can be met with in a moderate radius of London 
without diminishing the minimum, or dry-weather, flow of the streams. 
More than half a century has elapsed since the publication of Mr. 
Mylne’s first paper. Since then artesian and ordinary wells have been 
sunk in all directions, and previously to that date, doubtless, numerous 
others had been constructed in various parts of the country, some of them 
dating back to the Middle Ages. Your Committee would wish to speci- 
ally urge the Associated Provincial Societies to discover and preserve 
any early records of the sinking of wells that may be found in county, 
municipal, borough, or family documents, in county histories, and in the 
more recent papers of business firms using considerable quantities of 
water. Amongst the latter it is highly probable that numerous records 
of the daily or weekly variation in height of the water in their wells have 
been preserved. 
Continuous daily records of the height of the water of existing wells 
are much wanted, with the height of the surface above the Ordnance 
Survey datum. The height above datum of many of the wells, in refer- 
ence to which information has already been published in the preceding 
fifteen Reports, would much add to the value of the existing record ; 
such additional information could easily be got by many of the provincial 
societies. 
The record of water-level in the well at Odsey Grange, commenced 
by Mr. H. George Fordham, F.G-.S.,in November 29, 1878, unfortunately 
terminated on October 1, 1888, through his having to live abroad. Two 
other series of observations exist in the same area, viz. at Therfield Rectory, 
where a monthly record was commenced by the Rey. J. G. Hale on 
January 1, 1883, and is now continuing, and at Barley, where monthly 
observations were made by the late Mr. John Pearce, from January 1, 
1864, to October 1, 1886. 
West East 
WELL Odsey Grange, 2} | Therfield Rectory, | Barley 
miles | 44 miles 
Surface level 265 ft. 506 ft. 305 ft. 
Depth of well 104 ft. 276 ft. 165 ft. 
Well + or —O.D. | 161 ft. (+0.D.) 230 (+0.D.) 140 (+ 0.D.) 
Nearest spring E. of Ashwell, 13 | Litlington(Camb.),) Melbourn (Camb.), 
mile off 4 miles off 4 miles off 
Height of springs | 150 ft. 150 ft. - 150 ft. 
_ The springs rise on the outcrop of the horizon of the Totternhoe 
limestone, and feed the western branch of the Cam (or Rhee). Barley 
and Odsey are in the Cam Valley, Therfield on the ridge between it and 
the ni to the south draining into the Thames; the surface flow is in 
, AA 
