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EngliHi miles, will evaporate 33 millions of tons ; and 

 if the Mediterranean Sea be ellimatcd at 41b 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 1 60 fquare degrees of fea, and confe- 

 quently the whole Mediterranean muft lofein vapour 

 in a fummer's day, at leaft 52 So 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 fader 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 raifed, fee more 

 in Barometer, Cold, Dew, Heat, and Rain. 

 ' . For the effedt of Vapours in formation of fprings, fee 

 Springs, &c. .-.,... 



VA R I E G A T E D 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. Thofe 



. which are fpotted 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 j or at 

 leaft in the growing feafon, will have but a fmall ap- 

 pearance of 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 feafon, as they do in the other parts of 



the year. 



All the different forts of Variegation in plants were r 

 firft accidental, being no more than a diftemper in the 

 plant, which being obferved, has been cherifhed by im- 

 poverifhing the foil in which they grow, by which me- 



i thod their ftripes are rendered more lafting and beau- 

 tiful. But whatever fome perfons have affirmed of 

 ftriping plants by art, I could never obferve it done 

 by any, unfefs 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 Ihould 

 not grow, yet if they keep frefli but eight or ten 

 days, they will many times communicate their gilded 

 miafma to the fap of tlic trees into which they were 

 budded ; fo that in a fhort time after, it has ap- 

 peared very vifible in the next adjoining leaves, and 

 has been afterwards fpread over the greateft part of 

 the tree j but in fuch plants as are herbaceous, where 

 this operation cannot be performed, there is no way 



^ yet afceriained whereby this ftriping can be effefted 



by art. , ■ ■-,■ j^;'-^" ^" •■ >■'-■: -■■■- , ' ' '* 



In fome forts of plants this diftemper is often 'com- 

 municated to the feeds, fothat from the feeds gather- 

 ed from variegated plants, there will conftantly be 

 fome variegated plants produced ; as in the ftriped 



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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; fothat 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 ftieltered in the winter af- 

 ter they are become variegated, and are feldom of fo 

 long continuance j 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 oft^; 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 i which is efteemed the moft 

 beautiful ftriping, and which (when once thoroughly 

 cftablifhed) is hardly ever to be got out of the plants 

 again, fo as to render the leaves entirely green. . , ,^ 

 Kay, fuch is the venom of this morbid matter, that it 



not only tinges the leaves, but alfo the bark and frulf 

 of trees are infeded by it, as in the Orange, Pear, &c 

 whofe bark and fruit ai-e ftriped in the fame manner 

 as their leaves. 



The different colours which gppear in fiowers alfo pro- 

 ceed from the fame caufe, though it is generally in a 

 lefs degree in them than when the leaves and branches 

 are intefled: for the various colours which we fee in 

 the fame flowers, are occafioned By the feparation of 

 the niitrivite juice of plants, or from the alteration 

 of their parts ; whereby the fmallercorpufclcs, which 

 are carried to the furfaces of the flower leaves, are of 

 different forms, and thereby refledt the rays of light 

 in different proportions. In order to underftand this, 

 it may not be improper to fay fomething concerninc^ 

 the phenomenon of c9lours, as it hath been difco^ 



ve'fcd by the lace ' excellent philofopher Sir Ifa^c 

 Newton. 



1. Colour may be confidered two ways: (i.) As £l 

 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 itfelfj 

 which being fo modified, fliines upon the organ of 

 fight, and produces that fenfation we call colou°. . 



2. Colour is defined to be a property inherent irt 

 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, affefts the mind with different 

 fenfations. ■ . 



3. Again : colour may be defined a fenlation 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 refrangibiliry, and the magnitude of ita 

 component parts. '', .-, V r' y- / ; ;.. ;. 



4. According to the firft definition, light is the fub- 

 jedt of colour : accordinglto the latter it is the agent, 



5. So then light fometimes fignifies that fenfation oc- 

 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 opirtiohs of ancient and modem 



authors, and of the feveral fefts of philofophers, with 



/regard to the nature and origin of the phsenomenoa 

 colour. 



7. The peripatetics afltrt colours to be real qualities, ' 

 and inherent in the coloured bodies ; and fuppofe ■ 



that light doth only difcover them, but not any way^ 

 affeft their produdtion. 



'-.-v^v-^-r. 



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8> Plato thought colour to be a kind of flame con* 

 - fiftinVof'rhoft minute particles, very congruous to the 

 pores of the eye, and darted againft it from tlic 

 objed. ' - • ;- ' , -: 



■9^ Some rhoderns will have colour to be a kind of in- 

 ternal light of the more lucid parts of the objefl: dark- 

 ened, and confequently altered by the various mixtures 

 t)f the lefs luminous parts, \ ^ 



10. Others,_as did fome of .the antient atomifts, riiairi- 

 taih tolour not to be a lucid ftream, but a corporeal 

 efiluviup iflliing'otitof the coloured body. 

 II.' Others account for all colours out of the various 

 mixture of light and darknefs ; and the chemifts will 

 ^ have it forhetimds arife from the fulphur, and fome- 

 times ffprti the fait 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 

 of Ariftotle, who maintain, that colour is a property 



• inherent in tlie coloured body, and that it exifts with- 

 out any dependence on light, 



13. The Cartefiansi who made the fenfation of light 

 to be "the impulfe made on the eye by certain folid, 

 but very minute globules, eafiiy penetraririg the pores 

 of the air, and diaphonous bodic-s ; thefe derive colour 

 from the various proportion of the direfl: progrefs or 

 morion of thefe globules td theii* circumrotation or 

 morion round their own centres, by which means tliey 

 are qualified to ftrike the opric nerve, after diftin(^t 

 and divers manners, and fo produce the perception of* 

 divers colours, ■■ . • 



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14. They 



