APPENDIX C : STRATIFICATION OF HACKNESS HILLS 227 
it the tame at Suffield, Silpho and Broxa situated on the Hackness 
hills, but Suffield, originally the largest place of the three, had a supply 
for most of the year from a pond and shallow springs from the diluvium 
which also increased the depth of the soil on these rocky hills. 
The fine trees and hedges here and at Silpho so much higher than 
the naked but less exposed hills over the Derwent seem unaccountable 
until Geology unravels the mystery by finding that the better soil of 
these heights is derived from limestone. On principles common to the 
sites of population it appears that the three villages are each of them 
situated on the best soil of all the high land. The two farm houses on 
Suffield heights, and Tholso farm house also stand in the range of this 
best land which by investigation appears to be derived from an earthy 
parting in the limestone rock running through these places which though 
but thin fortunately occupies a good breadth of surface. 
Next to these superficial distinctions which render this greatly 
elevated plain strikingly different from any other portion of the Tabular 
hills, we may notice a character which it has in common with the whole 
range, viz., its well edged elevated contour, and the occurrence of Nab 
€nds therein which also are common to the outline of all the singular 
District, before noticed, between Harwood Dale and Newton Dale. 
They are well defined in Troutsdale, at Saltergate conspicuous at a 
great dis^^ance. Some may be seen in crossing the Vale of Pickering 
to Malton, and the singular features of more westerly points of these 
hills may be recognised from the walls of York. 
So extensively useful in Geology is the knowledge of contours 
that the great book of Nature is thereby laid open to us plain enough to 
read as we run. 
The detailed particulars of each stratum in Hackness hills as they 
range through the fields can only be interesting to the owner and 
occupiers of the land. Suffice it therefore to say that the stratum 
composed of whitish light blue and blackish beds of clay above the coaly 
Grit rock, which forms the sliding clifis of White Nab, South of Scar- 
borough ; is in Barnsclilf and other places around Hackness Island 
similarly characterised by slips, and wet strong land, everywhere grows 
oaks of the best quality but is commonly over saturated with water 
issuing from the rocks above. There are no sites of population on this 
stratum nor scarcely a building unless it fortunately happens to be 
covered with gravel. 
