3fel bourn 
Trans. Herts.Nat. Hist. Soc.,Vol.W,Pl.L 
Dunj r 'a mmxitif Sections across the outcrop of the Cholic irvNorthHerts , 
showing relation of underground Water-level to the Wells and Springs. 
1878-1888. 
4 _ 3 _ 2 _ 7 __ guiles 
wu = upper leret of Water. a b=lower levet of Water. X = Sea/ leveb- 
KGj: dell. 
F. SWeller, lith. 
