f 
-VAR 
Bhgliffl miles, will evaporate 33 millions of tons ; and 
if the Mediterranean Sea be eftimated at 410 degrees 
long, and four broad, allowances being made for the 
places where it is broader, by thofe where it is narrow- 
er, there will be 160 fquare degrees of fea, and conle- 
quently the whole Mediterranean muff lofe in vapour 
in a fummer’s day, at leaft 5280 millions of tons. 
In this quantity of Vapour, though very great, are 
only the remains of another caufe, which cannot be re- 
duced to rule ; that is, the winds, whereby the fur- 
face of the water is licked up, fometimes fafter than 
it exhales by the heat of the fun, as it is well known 
to thofe who have confidered thofe drying winds. 
For the manner wherein Vapours are railed, fee more 
in Barometer, Cold, Dew, Heat, and Rain. 
For the effedl of Vapours in formation of fprings, fee 
Springs, &c. 
VA RIEGATED fignifies ftreaked or diverfified 
with feveral colours •, of which there are now a great 
variety of plants in the gardens of the curious, whofe 
leaves are variegated with yellow or white. Thole 
which are lpotted with either of thefe colours in the 
middle of their leaves, are called blotched (in the 
gardeners term ;) but thofe whofe leaves are edged 
with thefe colours are called ftriped plants. Thofe 
plants whofe leaves are blotched are generally fubjeft 
to become plain, when planted in a good foil ; or at 
1 Tin. the gr'wfof r f‘n, will have but a fmall ap- 
pearance 01 the two colours ; but thofe which have • 
edged leaves, rarely become plain again, efpecially if 
the edging is broad, and goes quite through the 
leaves, though thefe do not appear fo finely variegated 
in the growing leafon, as they do in the other parts of 
the year. 
All the different forts of Variegation in plants were at 
firft accidental, being no more than a diftemper in the 
plant, which being obferved, has been cheriffled by im- 
poverilhing the foil in which they grow, by which me- 
thod their ftripes are rendered more lafting and beau- 
tiful. But whatever fome perfons have affirmed of 
ftriping plants by art, I could never oblerve it done 
by any, unlefs in woody fhrubs and trees, which may 
be variegated by putting in a bud or graft taken from 
a variegated plant ; where, although the buds ffiould 
not grow, yet if they keep frefli but eight or ten 
days, they will many times communicate their gilded 
miafina to the fap of the trees into which they were 
budded •, fo that in a ffiort time after, it has ap- 
peared very vifible in the next adjoining leaves, and 
has been afterwards ipread over the greateft part of 
the tree •, but in fuch plants as are herbaceous, where 
this operation cannot be performed, there is no way 
yet afcertained whereby this ftriping can be effefted 
by art. 
In fome forts of plants this diftemper is often com- 
municated to the feeds, fo that from the feeds gather- 
ed from variegated plants, there will conftantly be 
fome variegated plants produced •, as in the ftriped 
Wing Pea, the greater Maple, &c. therefore thefe 
may be conftantly propagated that way. 
That this ftriping proceeds from the weaknefs of 
plants is very evident, fince it is always obferved, that 
whenever plants alter thus in the colour of their 
leaves, they do not grow fo large as before, nor are 
they fo capable to endure the cold-, fo that many 
forts of plants which are hardy enough to endure the 
cold of our climate in the open air when in their na- 
tural verdure, require to be ffieltered in the winter af- 
ter they are become variegated, and are leldom of fo 
long continuance which is a plain proof that it is a 
diftemper in the plants, fince whenever they become 
vigorous, this ftriping is either rendered lefs vifible, 
or entirely thrown off-, efpecially (as was before ob- 
ferved) if the plants are only blotched, or if the edg- 
ing be of a yellow colour, it is lefs apt to remain 
than when it is white -, which is efteemed the moft 
beautiful ftriping, and which (when once thoroughly 
eftablifhed) is hardly ever to be got out of the plants 
again, fo as to render the leaves entirely green. 
Nay, fuch is the venom of this morbid matter, that it , 
VAR 
not only tinges the leaves, but alfo the bark and fruit 
of trees are infedted by it, as in the Orange, Pear, &c„ 
whofe bark and fruit are ftriped in the lame manner 
as their leaves. 
The different colours which appear in flowers alfo pro- 
ceed from the fame caufe, though it is generally in a 
lefs degree in them than when the leaves and branches 
are infedted : for the various colours which we fee in 
the fame flowers, are occafioned by the reparation of 
the nutrivite juice of plants, or from the alteration 
of their parts ; whereby the fmaller corpufcles, which 
are carried to the furfaces of the flower leaves, are of 
different forms, and thereby refle£t the rays of light 
in different proportions. In order to underftand this, 
it may not be improper to fay lomething concerning 
the phenomenon of colours, as it hath been difco- 
vered by the late excellent philofopher Sir Ifaac 
Newton. 
1. Colour may be confidered two ways : (1.) As & 
quality refiding in the body that is faid to be fo and 
fo coloured, or which doth modify the light after fuch 
a manner ; or (2.) as more properly the light itfelf, 
which being lb modified, llfines upon the organ of 
fight, and produces that fenfation we call colour. 
2. Colour is defined to be a property inherent in 
light, whereby, according to the different fizes or mag- 
nitudes of its parts, it excites different vibrations in 
the fibres of the optic nerve, which being propa- 
gated to the fenforium, affeifts the mind with different 
fenfations. 
3. Again: colour may be defined a fenfation of the 
foul, excited by the application of light to the retina 
of the eye ; and different, as the light differs in the 
degree of its refrangibility, and the magnitude of its 
component parts. 
4. According to the firft definition, light is the fub- 
je£t of colour : according to the latter it is the agent. 
5. So then light fometimes fignifies that fenfation dc- 
cafioned in the mind, by the view of luminous bodies ; 
fometimes that property in thofe bodies, whereby they 
are fitted to excite thofe fenfations in us. 
6. Various are the opinions of ancient and modern 
authors, and of the feveral feds of philofophers, with 
regard to the nature and origin of the phenomenon 
colour. 
7. The peripatetics affert colours to be real qualities, 
and inherent in the coloured bodies ; and fuppofe 
that light doth only difcover them, but not any way 
affed their produdion. 
8. Plato thought colour to be a kind of flame con- 
fifting of moft minute particles, very congruous to the 
pores of the eye, and darted againft it from the 
objed. 
9. Some moderns will have colour to be a kind of in- 
ternal light of the more lucid parts of the objed dark- 
ened, and conlequently altered by the various mixtures 
of the lefs luminous parts. 
10. Others, as did fome of the antient atomifts, main- 
tain coloui not to be a lucid ftream, but a corporeal 
effluvium iffuing out of the coloured body. 
1 1. Others account for all colours out of'the various 
mixture of light and darknefs ; and the chemifts will 
have it fometimes arile from the fulphur, and fome- 
times from the ialt that is in bodies ; and fome alfo 
from the third hypoftatic principle, i, e. mercury. 
12. The moft popular opinion is that of the followers 
pf Aiiftotle, who maintain; that colour is a property 
inherent in the coloured body, and that it exifts with- 
out any dependence on light. 
13. The Cartefians, who made the fenfation of Ifohf 
to be the impulle made on the eye by certain folid, 
but very minute globules, eafily penetrating the pores 
of the air, and diaphonous bodies ; thefe derive colour 
from the various proportion of the diretft proerefs or 
motion of thefe globules to their circumrotation or 
motion round their own centres, by which means they 
are qualified to ftrike the optic nerve, after diftimft 
and divers manners, and fo produce the perception of 
divers colours. 
1 3 R 
14. They 
