88 
J. HOPKINSON—LIST OP WORKS 
away altogether at Tring, in Hertford.” Mr. Hume appears to he 
unaware that Hertford is our county town. A similar mistake is 
made in referring to our Society as the “ Hertford Natural History 
Society.” In “A Revision of the Lower Eocenes” Mr. G. E. 
Harris only once mentions our county, and in his “Notes on the 
London Clay and its Deposition” Mr. J. S. Gardner does not allude 
to Hertfordshire at all. Both these papers appeared in the ‘ Pro¬ 
ceedings of the Geologists’ Association’ for 1887, and are of interest 
to Hertfordshire geologists. 
During the last few years much attention has been devoted to 
the superficial deposits, and several papers have been published 
by the Geological Society and the Geologists’ Association which 
give the results of investigations on these very variable beds within 
the area of which our county forms a part. The Geological Survey 
Drift maps of the whole of Hertfordshire have been published 
except one sheet, 46 S.W., in which is the north-west corner of 
the county. The survey of the superficial deposits of this area 
is completed, hut it may he a considerable time before the map 
appears. The London agent for the sale of the maps of the Survey, 
Mr. E. Stanford, received the first two copies of the Drift Map 
46 S.E., ostensibly published in December, 1898, about the middle 
of December, 1899, 
Many of the entries refer to works or papers which treat of the 
water-supply of London, a supply to which our county contributes 
an undue quota. One result of looking up the literature of this 
subject is that more than half the additions to the two former lists 
are of such works. The comparatively large number of recent 
references to it is chiefly due to the publication in 1893 of the 
Report of the Royal Commission on the Water Supply of the 
Metropolis, with its Appendices, etc., and to the interest in the 
subject to which this and the many Water Bills which have 
recently been brought before Parliament gave rise. This subject 
has so frequently and so recently (see Nos. 295 and 298) been 
brought before our Society, that I will only allude to three papers 
which show what erroneous and contradictory views are held as 
to the flow of water in the Chalk. 
In ‘A Paper on Bournes’ (No. 142) Mr. H. H. Erench says 
that the bournes north of the Thames rise in the same years as 
those south of that river, adding : “It is a most important point, 
too, that they rise only in those years, which shows that the vast 
underground sheet of water is continuous on both sides of the 
Thames, and even beyond.” Did they so rise it would only show 
that like causes give like results, each year’s or winter’s rainfall 
being much the same in the two areas, hut it would he a natural 
inference, were the continuity of the reservoir in the Chalk thus 
proved, that our Hertfordshire rivers might he depleted by an 
excessive amount of water being pumped from wells in Surrey, 
or “even beyond,” simultaneously with such pumping. They do 
not, however, for our Bourne has flowed several times when the 
Croydon Bourne has not, if Mr. French’s dates are correct. 
