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sides with a stratum of clay or very fat loam of a foot thick, 
that the spring water which is conducted to it may not strain 
through and run off. If the subsoil be loam or clay, the thick- 
ness of the stratum of clay to be placed upon it may be dimin- 
ished ; but, if it be a dry sand, it must be more than a foot 
thick. This artificial depression is then filled with earth artifi- 
cially prepared, and now the spring, or small brook is turned 
upon it. Truffles certainly require a moist soil, but they can- 
not endure boggy ground or standing water ; a ditch, must, 
therefore, be cut to carry away all su|)erfluous water. This 
ditch is either opened or shut accordingly as a superfluity or 
want of water renders necessary. But if, in very hot dry sum- 
mers, the supply of water should itself fail, the Truffle beds 
must be sufficiently moistened with pure river water. This is 
the expedient to which recourse must be had in dry situations, 
that neither possess a spring, nor a small brook for watering a 
plantation of Truffles. Since only small beds, and not large 
fields, are taken for the cultivation of Truffles, the greatest care 
may be taken in the preparatory steps, the expense of which will 
however, never be so considerable as to be much felt by the 
landed proprietor. A calcareous or chalky marl forms the 
groundwork of all artificial mixtures of soils for the cultivation 
of the Truffle. When this is to be had in the neighbourhood, it 
is mixed with the fourth part of iron sandstone. If this marl 
be not in the environs, then finely-beaten calcareous stone or 
beaten chalk must supply its place : to this must be added from 
the fourth to the third part of ferruginous sand, and the whole 
mixed together as uniformly as possible. With this artifi- 
cial calcareous marl the Truffle bed (which has been dug out 
from two and a half feet to three feet deep) is filled up a 
foot high, in the place of the natural earth. It is advantage- 
ous when the pit, which is dug out for that purpose, before it is 
filled with the new soil, is lined on the sides and bottom with 
unburnt calcareous stone. By this means not only will mice, 
and several kinds of worms, be prevented from establishing 
themselves in the new Truffle beds, and preparing to destroy 
the young germs of the Truffles, but sudden heavy rains will 
be prevented from occasioning an injurious mixture of the dif- 
ferent kinds of earth. Where calcai'eous stone is not to be had, 
sandstone may be used instead of it, especially if it contains 
