446 pliny's natural history. [Book XVIT. 



will gain nothing by approaching closer to its saline exhala- 

 tions. The same, too, is the influence exercised by rivers and 

 lakes ; they will either scorch the vegetation by the fogs they 

 emit, or else modify by their coolness the excess of heat. We 

 have already mentioned 29 the plants that thrive in the shade, 

 and in the cold even ; but in all these matters experience will 

 be found the best of guides. 



CHAP. 3. WHAT SOILS AEE TO BE CONSIDERED THE BEST. 



Next after the influences of the heavens, we have to treat of 

 those of the earth, a task that is in no way more easy than the 

 previous one. It is but rarely that the same soil is found 

 suited to trees as well as corn : indeed, the black 30 earth which 

 prevails in Campania is not everywhere found suited to the vine, 

 nor yet that which emits light exhalations, or the red 31 soil 

 that has been so highly praised by many. The cretaceous earth 

 that is found in the territory of Alba Pompeia, and an argil- 

 laceous soil, are preferred to all others for the vine, although, 

 too, they are remarkably rich, a quality that is generally looked 

 upon as not suited to that plant. On the other hand, again, 

 the white sand of the district of Ticinum, the black sand of 

 many other places, and the red sand as well, even though mixed 

 with a rich earth, will prove unproductive. 



The very signs, also, from which we form our judgment are 

 often very deceptive ; a soil that is adorned with tall and 

 graceful trees is not always a favourable one, except, of course, 

 for those trees. What tree, in fact, is there that is taller than 

 the fir ? and yet what other plant could possibly exist in the 

 same spot ? Nor ought we always to look upon verdant pas- 

 tures as so many proofs of richness of soil ; for what is there 

 that enjoys a greater renown than the pastures of Germany ? 

 and yet they consist of nothing but a very thin layer of turf, 

 with sand immediately beneath. Nor yet is the soil which 

 produces herbage 32 of large growth always to be looked upon as 

 humid ; no, by Hercules ! no more than a soil is to be looked 

 upon as unctuous and rich, which adheres to the fingers — a 



2 9 B. xvi. cc. 30, 31. 



30 A rick black mould, probably. 



31 A ferruginous argilla. 



32 It must of necessity denote a soil rich, in humus, though not, of 

 course, adapted for all kinds of cultivation. 



