282 
Farming of Buckingliamshire. 
Soluhle in Acids. 
Silica 4-18 
Oxide of iron G'TO 
Alumina 1-21 
Lime 5-97 
Magnesia 0'44 
Potass 1-15 
Soda l-(;4 
Carbonic acid 3'29 
Snlpliuric acid .. .. 1"G3 
rhosphoric acid .. .. 0"58 
26-79 
Insoluble in Acids. 
Silica 50-06 
Alumina 4-41 
Lime 0-57 
Magnesia 1-08 
Potass 0-99 
57-11 
Nitrogen in the soil 0-460 jiercent., 
equal to 0-560 ammonia. Of this 
nitrogen 0-0422 per cent, exists in 
the condition of salts of ammonia, the 
remainder 0-4178 being in the con- 
dition of nitrogenized organic matter. 
The essential ingredients of a good soil seem to be abundantly 
present here ; the proportion of organic matter (ammonia deriv- 
able from it) is large ; phosphates, sulphates, carbonates, and 
the alkalies the same. Again, from the abundance of decaying 
roots, and the quantity of sand (about 44 per cent.), the soil 
would possess a good mechanical condition. The learned Pro- 
fessor says, " I should be inclined to look upon it as a soil in 
which the materials are well adjusted ; " but adds, " whether the 
same composition might exist without fertility is another ques- 
tion." So chemistry is not very decided on the subject. Leaving 
the Vale of Aylesbury, and proceeding north, the Oxford clay 
spreads itself all over that unhappy portion of the county which 
lies within a line drawn through Buckingham, Stony Stratford, 
and Olney. It is a most expensive clay to cultivate, and is, 
therefore, chiefly in pasture. Some of these grass lands, ilignificd 
by courtesy with the name of pastures, grow nothing but rushes, 
and are decorated all over with tufts of hassock-grass and num- 
berless ant-hills. The uniform character of the clay is somewhat 
broken by patches of the Lickey Hill gravel, and also near its 
junction with the great oolite by beds of brasliy gravel, while 
about VVhaddon Chase and Winslow the gravelly wreck of many 
strata, but especially of the lower greensand, Ibrms a very dif- 
ferent sort of soil. From Marsh Gibljon to Steeple Claydon and 
Winslow there is hardly anything but poor wet clays. Above 
the latter town the debris of the ironsand gives to the land a 
reddish tint, while from thence to Bletchley there are hills of 
sand and flats of miserable clay. The whole of this district is 
used for dairying. 
The remainder of the land occupying the extreme northern 
limits of the county rests on the great oolite, Tliis stratum, 
when viewed generally, is regarded as one great oolitic mass, but 
in Bucks the upper parts of this formation, forming the acclivity 
of the hills which rise from the valleys of the Oxford clay, are 
