Cultivation of' Trujjics. 421 



the under and moister one lightly dug in, or, which is still 

 better, raked flat, lest the tender germs of the truffles should be 

 injured or destroyed ; but, when the truffle plantation is first 

 made, the whole cover must be deeply dug down. 



Every previous preparation is thus made for the cultivation of 

 truffles. We now come to the mode of causing them to be pro- 

 duced. Since they are neither sown, nor, like animals, propa- 

 gated by eggs and young ones, the only thing that remains for 

 us to do is, to cause the soil to produce truffles. We know from 

 experience that many forms (viz. crystallisations) are easily pro- 

 duced, when bodies of their own sort, already formed, are intro- 

 duced into the mass of forming matter. Thus, sugar easily 

 forms in crystals, when crystals of the same sort are hung in a 

 fluid mass saturated with saccharine matter. Fungi are also pro- 

 duced in a similar manner, where living bodies of the same kind, 

 or such as have not long been dead, or even parts of them lately 

 pulled off, meet with a soil adapted to them. Thus, mushrooms 

 thrive well if horse's or ass's dung be mixed with pieces of this 

 fungus. The same takes place with truffles ; only here greater 

 circumspection is requisite. 



The mushroom raises its head above the dark earth, and lives 

 and thrives in the open air, and in warm sunshine. When 

 taken from its parent soil, neither the operation of the circum- 

 ambient air, nor the gentle access of the sun's rays, immediately 

 destroys it. As long as its body contains sufficient moisture, it 

 continues to live, and may, without much precaution, be removed 

 from one place to another. If the journey does not last too 

 long, it still retains the degree of vitality necessary to impart to 

 the new soil the property of producing young mushrooms. On 

 this account, good mushroom beds, that are carefully made, 

 seldom fail, and the expectation of a good crop is constantly 

 justified. 



Not so the truffle. It cannot bear the immediate access of 

 the air, and still less of the sun's rays, but dies when it is ex- 

 posed to them, as quickly as a delicate fish when taken out of 

 the water, or an intestinal worm when torn from the animal body 

 which is its habitation. A dead body of a truffle, which, more- 

 over, soon becomes putrid, cannot, even under the most favour- 

 able circumstances, induce in the new habitat assigned to it a 

 formation of young fungi of its own species. This is possible 

 only to the living truffle : but its complete vitality is hardly suffi- 

 cient to give such a direction to the powers subsisting in the 

 strata of earth, as to produce and form new truffles in a soil that 

 had never produced them ; but, if this power of production is 

 once awakened, it is easy to retain it for years. 



If, therefore, truffles are to be transported from one situation 

 Ip another, and to be promoted to be the ancestors of their 



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