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Show E, ries they much fhorter refore the Sun warming the Atmofphere y-time bythe continual Influx of his y irs being once rais’d rion of fo In a long dry Seafon therefore, efpecially within the Yropicks, we muft have Recourfe, for fuffcient Moifture to keep Plants and Treesalive, to the moift Strata of Earth which lie next below that in which the Roots are. Now moift Bodies always communicate of their Moifture to more dry adjoining Bodies; but this flow Motion of the Afcent of Moifture is much ac But it is kno exceff > reflected DI ated by the Sun’s Heat to con- epths in the Earth, as is probable, ys, from the twentieth Experiment in the faid Book. th Now 180 Grains of Dew falling in one > fome fay, putable w regate fo as to form Clouc theSetting of Andthis j y being r. and th Day-time the f gr ing for much \ Heat of the E {pent it j very hot Clima The Ti b it {ca rce as Rain falls er Drops, les, in his In, it is pr y cooling the Air they and precipitate them ; and becaufe or this Reafon the Eveni here and ther ng feldomfail to be may be otk > U find out the Quantit Night on the fifteen moift Earth, Ground, and t -fs’d, when the the Atmofphere pours, which have in the preceding mthof the Ez rains; and decreas’ on of the Day the A e, and fpend the ‘ire on the cold moift Air that they pafs through. Hence i are more copious Seafons, there being Vapour in Readinefs, by r but a {mall Expence thereof during the Winter’s Cold and Froft th ther Times. 1 by Experience, that the Dews are 1 hotter Countries thanincold, as B SummerNightsin Africa, i ; the Reafon as to be this, that in the Dayeat of the Sun raifes abundance of of the Water ; which V apours are rarefy’d by the fame Heat, that rs’ far and wide; but the Cool 3s them together, and con- : Degree that they fall to _ Ground, but not in fuch large Drops as R in does: But in colder Countries, where r nt Rains, and the Vapours are y d, mott of them come downin Rain, a {mall Part turns to Dew. Befides, a there is a great Difference between is, the more Dew falls on it in a} hana double Quantity of De Ils on a Surface of Water than there does on an equal Surface of moift Earth: The Ev poration of a Surface of W in nine Hours Winter’s dry Day, is Inch: The Evaporate of a Surface fet in the Shade during a nine Hours Day, 4 Part ofan Inch = 7774254. He adds, that he 1890 found the Dew in a Winter Night to be the 4m Part of an Inch; fo that if we allow 151 Nights for the Extent of the Summer Dew, it will in that time arife to one Inch Depth : And reckoning the remaining 214 Nights for the Extent of the Winter’s Dew, it will produce 2,39 Inches Depth; which makes the Dew of the whole Year amount to 3,39 Inches Depth. Andthe Quantity which evaporatedin afair Summer’s Day from the fame Surface, being, as1O 282 Grains, gives Part of anInch Depth for Evaporation, which is four times as much as fell at Night. he took two glaz’d if Night on a Circle of a Foot Diameter = 113 fquare Inches; thefe 1§0 Grains being equally fpread on this Surface, its Depth will be — 159 are 540 Grains more evapora from the Earth every 24 Hours in Summer thanfall in Dew in the } ght; that is, in 21 Days near 26 Ounces from a circular Area of a Foot Diameter ; and Circles being as the Squares of their Diameters, 10 Pounds, =p 2 Ounces will in 21 Days be evaporated from Inch; fo the Evaporation of a Surface of Water is to the Evaporation of a Surface of Summer as 10:3. antity of Rain and Dewthat falls in Medium 22 Inches: The Q: s Evaporation ina Year is at ince that is the Rate at summer’s Day: From hes is to be deduéted 3, 39 ulating daily Dew, there re] ich 6,2 Inches dedu@ity of Rain that falls in at leaft 16 Inches Depth, 1 Moifture for s and Earth ever fuffers for 15 Inches Depth, even in the drieft Seafons in this Country IA Water for the Springs, befides great Supplies from much moré plentiful Dews than fall in plain Countres s which vaft Stores feem fo abundantly fuficient to anfwer the great uantity of Water, which is convey’d away by the Springs and Rivers fromthofe Hills, that we need not have Recourfe for Supplies to the great Abyfs, whofe Surface at high Water is furmounted fome hundreds of Feet by thofe vaft Hills from whence the longeft and greateft Rivers take their Rife. DIAPENSIA; vide Sanicula. DICTAMNUS ALBUS; vide Fraxinella, DICTAMNUS; [DfldurG-, of & mxTay, to being forth, becaufe this Plant is good to Dittany. The Charaéfers are ; The Flower-cup confifts of two Leaves ; after that another athwart the former; and again, a third in like manner, until a fealy Head be thence form’d: Out of the Center of all thefé Scales grows a Flower, roundifo, and bifid: whofe Creft is erett, The Beard is divided into three Parts: Thefe little Flowers come forth from leafy Scales after the manner of the Verticle Plants, in a long loofe Spike. The Szecies are 5 1. Dicramnus 3 Creticus. C. B. Dittany of Crete. 2. Dieramnus; montis Sipyli, origani foif, lor. Bat. Dittany trom Mount Sipylus, with wild Marjoram Leaves. The firft of thefe Plants hath been renown’d for many Ages, upon the Account ofits fovereign Qualities in Medicine. This is generally brought overdry from the Levant, and is ftill us’din fome of the grand Preparations, This Plant, although a Native of a warmer Country thanours, yet is tolerably hardy, and will endure the Cold of our common Winters, if planted in the open Air, provided it is planted in a dry fandy Soil: It may be propa- gated byplanting Cuttings in any of the Sume Cafe of mer Months; which muft be fhadedand water’d the Hemifphere of 30 Inches Diameter, which the Sun-flower’s Root occupi ; which, with the 29 Pounds drawn off by the Plant in the fame Time, makes 39 Pounds, that is, 9 Pounds and 2 out of every Cubick Foot of Earth, the Plants Roots occupying more than 4 Cubick Feet: But this is a much greater Degree of DrinefS than the Surface of the main 35 Inches Depth of promote Child-birth.] Fe fays likewife, that he foundby the fame Means, the Evaporation of a Winter’s Day to be nearly the fame as in a Summer’s Day ; for the Earth being in Winter more faturate with Moifture, that Excefs of Moifture anfwers to exceflive Heat in Summer. Cruquius, N° 381. of the Philofophical lions, found that 28 Inches Depthevaorated in a whole Year from Water, i. e. 45 fan Inch each Day at a mean Rate: But the Earth in a Summer’s Day evaporates 4. of an I Springs, which are more or lefs exhaufted, according to the Drinefs or Wetnefs of the Year. Hence we find, that 22 Inches Depth of Rain in a Year, is fufficient for all the Purpofes of Nature in fuch flat Countries as that about Teddington near Hampton-Court: But in the Hill Countries, as in Lancafbire, therefalls 42 Inches Depth of Rain-water: From which deduéting 7 Inches for Evaporation, there re- is ninth Exicks, that until they have taken Root: afterwards they m the Hops, Border under a South Wall, whereit will rein for feveral Years, unlefs deftroy’d by ~ an Inch each Day f w’d 6,2 Inches to fthe Ground; which added I hich is the utmoft \ of HopDepth Inches to fupply may be either planted in Pots, or ina warm iolent hard Frofts ; for which Reafon °tis advifeable always to keep a Pot or two ofthis Plant under a Frame as a Referve, in cafe thofe abroad fhould be deftroy’d. produces its Flowers in This Plant Zune and Fuly, but the Seeds are feldom perfected in this Climate: And altho’ there is no great Beauty in the Eee Flowers |