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Means the younger Branches and 

 Leaves have been rendred toe weak 

 to endure the open Air when they 

 are expos'd to it, which has often 

 proved of worfe Confequence to 

 Trees, than if they hadremain'd in- 

 tirely uncovered. 



Whereas when the Covering be- 

 fore mentioned has been perform- 

 ed as it ought to be, it has proved 

 very ferviceable to Fruits j and 

 many time?, when there has been 

 almofl: a general Deftrudion of 

 Fruits in the neighbouring Gar- 

 dens, there has been a Plenty of 

 them in fuch Places where they 

 have been covered : And tho' the 

 Trouble may feem to ibme to be 

 very great, yet if thefe Coverings 

 are fix'd near the Upper-part of 

 the Wall, and are faftened to Pal- 

 lies, fo as to be drawn up or let 

 down, it will be fbon and eafily 

 done, and the Succefs will fuffici- 

 ently repay the Trouble. 



But there is another Sort of 

 Blight that fometimcs happens later 

 in the Spring;, i>iz,, in April or May, 

 which is often very deilruclive to 

 Orchards and open Plantations, and 

 againft which we know of no Re- 

 medy. This is what is cali'd a 

 Fire BlaJ}, which in a few Hours 

 hath not only deilroy'd the Fruit 

 and Leaves, but many times Parts 

 of Trees, and fometimes whole 

 ones have been kiil'd by it. 



This is fuppofed to be efPedfed 

 by Volumes of tranfparent flying 

 Vapours, which among the many 

 Forms they revolve mto, may 

 fometimes approach fo near to a 

 Hemifphere, or Hemicylinder, cither 

 in their upper or lower Surfaces, 

 as thereby to make the Beams of 

 the Sun converge enough to fcorch 

 the Plants or Trees they fall upon, in 

 Proportion to the greater or lefs 

 Convergency of the Sun's Rays, 



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The learned Boerhaave, in his 

 Theory of Chymijlry , obferves, 

 " That thofe white Clouds which 

 " appear in Summer-time, arc, as 

 " it were, fo many Mirrors, and 

 " occalion excelUve Heat ; thefe 

 " cloudy Mirrors are fometirnes 

 " Round, fometimes Concave, Po- 

 " lygonous, ^r. When the Face 

 " of the Heavens is covered with 

 " fuch white Clouds, the Sun Ihin- 

 *' ing among them muft of Ne- 

 " celTity produce a vehement Heat, 

 " fince many of his Rays, which 

 " would otherwife, perhaps, never 

 " touch our Earth, are hereby re- 

 " flecied to us ; Thus, if the Sun 

 *' be on one Side, and the Clouds 

 *' on the oppolite one, they will 

 " be perfed: Burning GlafTes : And 

 " hence the Phaenomena of Thun- 

 " der. 



*' I have fometimes, continues 

 *' he, obferv'd a kind of holiov* 

 " Clouds, full of Hail and Snow, 

 " during the Continuance of which 

 " the Heat was extreme, iincc by 

 *' fuch Condcnfation they were 

 «' enabled to reflect much more 

 " ftrongly : After this came a fharp 

 *' Cold; and then the Clouds dii- 

 " charg'd their Hail in great Quan- 

 " tity, to which fucceeded a mo- 

 " derate Warmth. Frozen Con- 

 *• cave Clouds therefore, by their 

 " great Reflexions, produce a vi- 

 " gorous Heat, and the iame, when 

 " reiolv^d, exceflive Ccld. " 



Vv^'hcnce (as Mr. Hales obferves) 

 we fee, that Blafts may be occa- 

 fion'd by the Refledfions of the 

 Clouds, as well as by the above- 

 mentioned Refradlion ofdenic tranf- 

 parent Vapours. 



Againil: this Enemy to Fruits, 

 ^c. as hath been faid, there is no 

 Guard to our Plantations, nor any 

 Remedy to cure it ■■, but as this 

 more frequently happens in clofe 



Plan- 



