VOR uGaR DENN G. | 695 
. q Osob. an old Wall. The lower Leaves were ftain’d; | are hence known with Certainty; and this Ef- Oéeb. 
yellow. — a. y 
In both thefe Cafes the Retnains of Mortar 
? 
that is, a Mixture wherein Lime was a principal 
Ingredient, was in the Caufe ; and from the two 
parallel Cafes, there. is ground to fuppofe it had a 
oreat Share in producing the Effect. 
The Dulcamara was a weak Plant, but the 
Leaves, except in Colour, unalter’d; the Nettle 
grew flrongly enough, but the Leaves were longer 
than ufual, and narrower. 
It appears from this, that the fame Caufe which 
ftain’d the Leaves, alfo affected the general Growth 
of the Plants, weakening the one, and altering the 
Leaves of the other. 
This Nettle, in earlier Times of Botany, would 
have been called a new Species. ‘The Footftalks 
of the Leaves in the Nettle were alfo itreaked 
with yellow, but not thofe of the Dulcamara. 
This Accident, however, is not particular, for 
in fome variegated Jafmines the young Shoots 
are ftain’d; and in fome Fruit Trees even the 
Rind of the Fruit. . 
In the Marfhes not far from Thorndon, the 
Seat of the Lord Petre, we obferved fome 
and a few of the upper: the Colour a ftrong | fect of them is correfpondent with the general Opi- 
nion and Experience of thofe who have examin’d 
into the Subject. 
Mr. Ray determines, that the blotching and 
ftriping of Leaves, is the Effect of a diftemper’d 
Condition of the Plant; and he mentions Lime 
as the Caufe; and the Experiments of thofe who 
have try’d Lime Water and Brine feparately on 
' growing Plants, fhew that they take a like Ef- 
fect. 
It is not to be fuppofed, that the Variegatioris 
of Leaves can, in a regular Manner, be brought _ 
on by fimple Watering. with a medicated Liquor ; 
but the Effect of thefe has been turning the 
Leaves altogether yellow, and afterwards deftroy- 
ing the Plants: both Lime and Salt are good © 
‘Manures, but this is no Objection to the prefent” 
_ Opinion. 
For that Purpofe they ate to be mix’d in very 
fmall Quantities with the Earth: but when they 
form. the greater Part of the Nourifhment,. they 
make the Plant fade; and a Change of green 
into yellow is the firft Operation. 
The Gardener has here the Principles of the 
Plants of the Meadow {weet near the Ditches of Variegation of Leaves, and the feveral Caufes : 
Salt Water; and in thefe the Leaves were often 
irregularly blotch’d, and ftain’d with yellow. 
From thefe Obfervations it appears probable, 
that befide want of Water, and a rich Soil, 
which were deficient in both the Inftances, the 
and: variegating the Leaves of Plants, are Lime 
he fees what Plants are, how conftructed, and 
what thofe Ingredients in a Soil are, that tend to 
alter the Colour of the Leaves; From this the 
Practice may reafonably be attempted ; and on 
thefe Principles alone it can: for the Search muft 
two greateft known Efficients for the ftriping | be fought in the Nature of Vegetables, and the © 
Laws of Vegetation; not in the Newtoman Doc- 
and Sea Salt. There may be others: but thefe | trine of Light and Colours, 
CHA P. IV. 
The Method of Prattice. 
| Be T the Gardener recapitulate in his Memory 
the Principles we have juft deduced from 
Obfervation, and he will find, that if there be 
not a Certainty, there is at leaft a fair Profpect 
of bringing on the Variegation of Plants at his 
Pleafure ; and will learn in what manner to at- 
tempt it. : 
He will remember that the Colouring, whe- 
ther in Blotches or Streaks in the Body of the 
Leaf, or in an Edge round the Circumference, is 
the Effect of a difeafed State of the Plant: 
that the Glands are the diftemper’d Part; and | 
that Lime and Salt are two Ingredients known to 
affift in bringing on this Change. 
He fees that the Seeds of Plants contain in 
their Heart the Rudiments of the Glands, for the 
Plant that is to grow from them; and that if the 
diforder’d State of thefe Glands can be brought 
3 
on in the lower Part of the Plant, tlie Confe- 
quence muft be the continuing it by proper Ma- 
nagement throughout; for the Leaves and Branches 
all are produced from the extream Fibres of the 
Pith. | 
Therefore far from depending upon Layers, 
Cuttings, or Budding, though all thefe Ways 
may take Effeét, the true Method is to begin with 
the Seed. 
The Means will be a proper Compoft for 
the Plants; a Liquor for fteeping the Seed be- 
fore fowing; and a Water impregnated with the 
fame Ingredients, for nourifhing it in the Growth; 
which muft, by an artful Method, be convey’d 
immediately to fome part of the glandular Struc- 
ture, not altogether fent in by the common Courfe 
of the Fibres from the Root. 
‘The Compoft muft be barren in its Nature, . 
and 
