L U P 
part of an inch deep, befides what evaporated from 
the earth . 
And this quantity of moifture, in a kindly ftate of 
the air, if daily carrried off, is a fufficient quantity to 
keep the Hops in a healthy ftate ; but in a rainy moift 
ftate of air, without a due mixture of dry weather, 
too much moifture hovers about the Hops, fo as to 
hinder, in fome meafure, the kindly perforation of 
the leaves, whereby the ftagnating fap corrupts, and 
breeds mouldy fen, which often fpoiis vaft quantities 
of flourifhing Hop-grounds. 
This was the cafe in the year 1723, when for ten or 
fourteen days almoft continual rains fell, about the 
latter half of July, after four months dry weather, 
upon which the molt flourifhing and promifing Hops 
were all infeCted with mould, or fen, in their leaves 
and fruit, while the then poor and unpfomifing Hops 
efcaped, and produced plenty, becaufe they, being 
fmall, did not perfpire fo great a quantity as others, 
nor did they confine the perfpired vapour, fo much 
as the large thriving Vines did in their Ihady thickets. 
This rain on the then warm earth, made the Grafs 
fhoot out as faft as if it were in a hot-bed, and the 
Apples grew fo precipitately, that they were of a flafhy 
conftitution, fo as to rot more remarkably than had 
ever been remembered. 
The planters oblerve. That when a mould, or fen, 
has once feized any part of the ground, it foon runs 
over the whole, and that the Grafs, and other herbs 
under the Hops, are infeCted with it, probably, becaufe 
the fmall feeds of this quick-growing mould, which 
foon come to maturity, are blown over the whole 
ground j which fpreading of the feed may be the 
reafon why fome grounds are infeded with fen for 
feveral years fucceflively, viz. from the feeds of the 
laft year’s fen. Might it not then be advifed to burn 
the fenny Hop-vines, as foon as theHops arepicked, in 
hopes’thereby to deftroy fome ofthe feed of themould? 
Mr. Auften, of Canterbury, obferves fen to be more 
fatal to thofe grounds that are low and flickered, than 
to the high and open grounds, to thofe that are {helv- 
ing to the north, than to thofe {helving to the fouth •, 
to the middle of grounds than to the outfides ; to the 
dry and gentle grounds, than to the moift and ftiff 
grounds. 
This was very apparent throughout the plantations 
where the land had the fame workmanfhip and help 
bellowed upon it, and was wrought at the fame time. 
But if in either of thefe cafes there was a difference, it 
had a different effecft, and the low and gentle grounds, 
that lay negledted, were /then feen lefs diftempered 
than the open and moift, which were carefully ma- 
naged and looked after. 
The honey dews are obferved to come about the nth 
of June, which, by the middle of July, turn the 
leaves black, and make them ftink. 
The faid Dr. Hales relates, That in the month of 
July (the feafon for fire-blafts, as the planters call 
them) he has feen the Vines in the middle of the Hop- 
ground fcorched up almoft from one end of a large 
ground to the other, when a hot gleam of fun-lhine 
has come immediately after a fhower of rain, at which 
time vapours are all feen with the naked eye, but eft 
pecially with reflecting telefcopes, to afcend fo plenti- 
fully as to make a clear and diftinCt objeCt become im- 
mediately very dim and tremulous ; nor was there 
any dry gravelly vein in the ground along the courfe 
of this fcorch ; it was therefore, probably, owing to 
the much greater quantity of fcorching vapours in the 
middle, than the outfides of the ground, and that be- 
ing a denfer medium, it was much hotter than a more 
rare medium. 
And, perhaps, the great volume of afcending va- 
pours might make the fun-beams converge a little 
towards the middle of the ground, that being a den- 
fer medium, and thereby increafe the heat confide- 
rably ; for he obferved. That the courfe of the 
fcorched Hops was in lines at right angles to the fun- 
beams about eleven o’clock, at which time the hot 
gleam was. 
The Hop-ground was in a valley which rati from 
fouth-wefl: to north-eaft, and to the beft of his re- 
membrance* there was but little wind, and that in the 
courfe of the fcorch •, but had there been fome other 
gentle wind, either north or fouth, it is not improba- 
ble but that the north wind gently blowing the vo- 
lume of rifing wreak on the fouth fide of the ground,, 
that fide might have been moft fcorched, and fo vice 
verfa. 
As to particular fire-blafts, which fcorch here and 
there a few Hop-vines, or one or two branches of a 
tree, without damaging the next adjoining, what 
aftronomers obferve, may hint to us no very impro- 
bable caufe of it, viz. They frequently obferve (eft 
pecially with reflecting telefcopes) fmall feparate por- 
tions of pellucid vapours floating in the air, which, 
though not viiible to the naked eye, are yet confide- 
rably denfer than the circumambient air ; and va- 
pours of fuch a degree of denfity may very probably 
either acquire fuch a fcalding heat from the fun as 
will fcorch what plants they touch, efpecially the more 
tender. 
(An effeCt which the gardeners about London have 
too often found to their coft, when they have incau- 
tioufly put bell-glaffes over their Cauliflowers early in 
a frofty morning, before the dew was evaporated off 
them •, which dew, being raifed by the fun’s warmch, 
and confined within the glafs, did there form a denfe, 
tranfparent, fcalding vapour, which burned and killed 
the plants :) 
Or, perhaps, the upper or lower furface of thefe 
tranfparent, feparate, flying volumes of vapours, may, 
among the many forms they revolve into, fometimes 
approach fo near to an hemifphere, or hemicylinder, 
as thereby to make the fun-beams converge, fo as of- 
ten to fcorch the more tender plants they {hall fall on, 
and fometimes alfo parts of the more hardy plants and 
trees, in proportion to the greater or leffer conver- 
gency of the fun’s rays. 
The learned Boerhaave, in his Theory of Chymiftry, 
p. 245, Shaw’s edition, obferves, That thofe white 
clouds which appear in fummer time, are, as it were, 
fo many mirrours, andoccafion exceflive heat, Thefe 
cloudy mirrours are fometimes round, fometimes con- 
cave, polygonous, &c. When the face of heaven is 
covered with fuch white clouds, the fun Alining 
among them, muff, of neceffity, produce a vehement 
heat, fince many of his rays, which would otherwife, 
perhaps, never touch our earth, are hereby reflected 
to us. Thus, if the fun be on one fide, and the 
clouds on the oppofite one, they will be perfeCt burn- 
ing-glaffes, and hence the phenomena of thunder. 
I have fometimes (continues he) obferved a kind of 
hollow clouds full of hail and fnow, during the conti- 
nuance of which the heat was extreme, fince, by fuch. 
condenfation, they were enabled to refleCt more 
ftrongly. After this came a {harp cold, and then 
the clouds difcharged their hail in great quantity, to 
which fucceeded a moderate warmth, Frozen con- 
cave clouds, therefore, by their great reflexions, pro- 
duce a vigorous heat, and the fame, when refolved, 
exceflive cold. 
From which the Rev. Dr. Flales obferves as follows : 
Hence we fee, that blafts may be occafioned by the 
reflexions of the clouds, as well as by the above-men- 
tioned refraction of denfe tranfparent vapours. 
About the middle of July Hops begin to blow, and 
will be ready to gather about Bartholomew-tide. A 
judgment may be made of their ripenefs, by their 
ftrong fcent, their hardnefs, and the brownifls colour 
of their feed. 
When by thefe tokens they appear to be ripe, they 
muft be picked with all the expedition poflible j for 
if at this time a ftorm of wind fliould come, it would 
do them great damage, by breaking the branches, and 
bruiflng and difcolouring the Hops • and it is very 
well known, that Hops, being picked green and 
bright, will fell for a third part more than thofe 
which are difeoloured and brown. 
