132 Tlie Ariricultural Relations of the Western Portion 
The presence of iron, however, spoils it for that purpose. By 
mixture of these clays, with lime or chalk, the salts of iron would 
be decomposed, with production of sulphate of lime. 
Here, then, we have several of the constituents of plants, in 
which the neighbouring siliceous sands and gravels are generally 
deficient. 
The improvement of Mr. Calcraft's heathland before men- 
tioned was effected by means of this clay and liming, in addition 
to draining. I saw some of the white clay spread on reclaimed 
heathland near Lytchet, and was informed that it was found bene- 
ficial. I saw spread on a field between Christchurch and Bourne- 
mouth some of the dark sandy clay, which is frequently asso- 
ciated with the white clay, and was informed by a ploughman, 
"who was at work in the field, that the benefit was visible to an 
inch on the subsequent crops. In a brick-field between Poole 
and Bournemouth I inquired if the same dark sandy clay, dug 
there for bricks, was ever used for the land, and was informed 
that it did no good, but that the white clay was sometimes applied 
to garden-ground, and with evident advantage. 
On the unreclaimed heath near the clay-pits I also observed a 
much better vegetation where the rain-water had washed some 
particles of clay from the spoil-banks over the turf. 
Supported by these facts, and by my knowledge of the com- 
position of these clays, and of the deficiencies of the soils of the 
neighbourhood, I did not hesitate to recommend several farmers 
and landowners to make experiments with them, both alone, and 
mixed with chalk or lime. 
I also heard of instances in which the Barton clay of the Middle 
Bagshots had been tried as a dressing for the neighboui'ing light 
soils, but the reports of its effects were by no means favourable. 
The marls of the freshwater series were considered preferable, 
even brought from a greater distance. The clay, however, was 
used alone ; if it had been mixed with chalk or lime the results 
would probably have been different. The clay and marl Avhich 
have wrought such a change in the poor soils of Norfolk, raising 
them from an annual value of less than 2>s. an acre to more than 
20s., consist either of simple chalk, or a natural mixture, in vary- 
ing pnjportions, of clay and fragmentary chalk. 
Some of the agriculturists of Hampshire and Dorsetshire, to 
whom I communicated these views, expressed an intention of 
trying the experiments which I recommended ; but in the locali- 
ties where the clays of the Lower Bagshots are most abundant, 
and most easily obtainable, great doubts were in general enter- 
tained respecting their value for the improvement of the soil : 
and a preference was expressed for the "fat" marls of the New 
Forest, with regrets that they were not accessible. That they 
