106 
the florist’s journal. 
This extra vigour imparted to strange plants is, however, only 
temporary ; for, in a few years, the plants, or their progeny, become 
naturalized, and are no longer so much excited by the change of 
air and soil as they appear to be at first. We may easily and 
rationally imagine that soil in which the same kind of plant never 
grew before may be replete with nutritive matter favourable to the 
stranger, and hence its extra vigour; but how a change of air without 
reference to any appreciable difference of temperature can effect 
similar results, is not so easily guessed. But it has been proved, 
that seeds or plants removed from one soil to another of exactly 
the same description, but at some distance from each other,— 
either longitudinally or in different parallels of latitude, not too 
far from the middle of the temperate zone,—become renovated, 
and advance with more celerity than if they had not been trans¬ 
planted ; and this they continue to do, though only for a few years. 
In considering the aptitudes of wild plants, we see them dis¬ 
tributed according to the nature of the soils most suitable to 
them. For instance, a clayey soil is the natural habitat of the 
Coltsfoot; a calcareous or chalky soil is known by the prevalence 
of the Spiked Speedwell and the Little Bed-straw ; a flinty soil 
nourishes the Three-leaved Speedwell and the Viper’s Bugloss; 
the Common Sorrel and Sheep’s Sorrel inhabit ferruginous 
gravels; while Heath, and Spurrey, and Septfoil, are common on 
dry peat earth ; Glass-wort indicates a saline soil; and the Marsh 
Marigold a moist one ; and very dry sand bears the Sheep’s Sorrel, 
Wild Thyme, and Red Sand-wort. Thus it appears, that the 
nature of the soil fixes the locality of the plants above mentioned. 
But beside these geological attractions for certain tribes of plants, 
there are others which appear to be particularly affected by the 
density of the air. Auriculas never thrive in low damp situations; 
they are natives of the Alps, where the air is pure and rare : and 
many other plants are similarly constituted. The density, dryness, 
and temperature of the air, are its only properties that, we imagine, 
can materially affect the health of plants ; for though it may often 
be tainted with fuliginous or other noxious vapours, especially near 
large towns, it is never so much so, as to differ much in general 
properties over the whole face of a country. 
A Rose-tree planted in the near neighbourhood of London 
continues to thrive only a very short time ; but if it be removed to 
Hounslow Heath, it will gain fresh vigour and become a healthy 
