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Show 120 Of the Flying of Birds. Chap. XX. Chap. X X. 0f the Flying of fBirt/s, . 12 I "'ii'vi'v'i-‘m- Addufiors of the Shoulder Bone, upon the Fluid Air, impelling their back 2,1,] $5531", part like :1 Stern governed by their Train, as by a Rudder, by which Birds ‘f'ilmii'gli‘ii' Rear their courfe in the troubled Air, forward, or toward the right or left, ;,,",‘,;‘,},°nfi,, accordino to the Diéiates of their Phancy: And are in no CapaCity to m" flight fly \Vitllmthcir Tails forward, becaufe they will then want theconduc} of their Trains, which regulate the motions of their Body and Wings, whofc Th'fimfiiinsr repeated ftroaks carry the Head forward. . . Bfrfiflliozf it So that the motion of Flying is celebrated (as I conceive) after this: man. hmm‘mm' net: Firft, The Wings being {h‘etched out and expanded by the lt‘nfors of the Cubit, and third Joint, keeping them in a kind of uniform Pol-hire, in whichthe \Vings being hollow underneath, are receptive of a large pl‘0~ portion of Air filling their lower Surfaces, beautified With three ranks of Feathers, of which, the Quills are the mofl' long and large lodged in the outward mai‘gcnts of the Wings, and upon which ( being boied up by Inany Columns of Air) the weight of the body of the Fowl is chiefly fuppor. ted. and the expanded Wings being drawn downward and backward, in the‘form of aMinute Arch, by the Adduétors of the Shoulder Bone, to nive them the advantage of the fironger appulfe upon the Ambient Air, iixhich giving a refiftence to the brisk motion of the Wings, do (boot the body forward, caufed partly by the force of the Wings Hriking the Air ( by whofe Benitence the body of Birds is darted forward ) and partly by theFla‘ick power of the Air, which being firongly comprelled, by the vibration of the Wings, doth fpeedily again Expand it felf like a Spring, and by a kind of Current, dorh help the body of Fowls to fwim forward in a fluid Medium. Birds having not exaé'tly a round Fabrick of body, in reference to their length, feem to be fornewhat of a Pyramidal Figure, fmall in the Anterior Region (rcfembling a kind of Cone) and larger in the Pofterior, \thch reprcfcnteth fomewhat ofa Bafe: And being fupported, by an equal furface of Feathers, encircling the Body, the Head doth part the foft Coinpage of Air, moving forward in a flraight courfe, which Birds do eafily aecomplilh by retraéting their Thighs, Legs, and Feet, near their Bellies, night is M or lower regions of their Bodies, to compofe them into a round Figure, as nagcdbyion- thereby rcndring them more capable of Motion, which is performed by at r. r . . . i Aiiidiiutlezby fanning the Air into a thicknefs , caufed by the frequent [iroaks of the fifgdlffbf the Wings, made by the Elevations of them by the Scapular Mufeles, and by mks-52:35, their Depreflions produced by the contraéiion of the Adduétors (relating andAdtlu- to the Bones of the Shoulders) pulling the Wings downward, which are am enwrapped within the foft vefiments of Feathers, as fo many fine Contex- tures, confifting of light hollow Bodies, big with Air. And becaufe Feathers are often expofed to great Ptorms and lhowres, Nature hath molt wifely ordered their firuéture with great Artifice, that their more inward and fpungie Entrals, lhould be fecured within the firm confinement of morefolid Membranes, and thin horny Integunients: 5‘0 that Nature, though different in its parts, yet is of an amicable Temper, and full of Harmony, reconciling foft and fpungie with hard and compact Bodies, from which the mol't fmall, light, and numerous procetl'cs of Feathers do fprout. The Feathers lodged in the upper Region of the bodies of Birds, are longer and greater to undergo the Violence of Encounters above , and more foft below, as fit for the reception of greater proportions of Air, to fupport die Body in Motion, which is chiefly effected by Wings, made 11;; o of a trebble rank of Feathers; the chief and greatef‘t are {tiled (mills, to $3353", make Contuflions, and Fannings of Air, to comprefs it into a clofer Con~ 17:33:" globated body, to boy up, and jirk the Body forward in Progreflive Motin ' H on. And thofe leifer rows of fmall Feathers, do atreft the Air within their Cavities, to prevent its over-hafty efcape, while the firfi rank expandeth the Wing ', in which the grand Architeél: hath two main defigns in the fine light coverings of Feathers, that by them a weighty body might float in a move-able fluid Medium, and thence be tranfported from place to place, for its pleafure and advantage: Upon which account, a folid Fabrick, compofed of divers Integral parts, could not be any way managed in Flying, without the addition of fome light Enclofures (affixed to a heavy Body, full of hollow and aery Particles) to which the fanned and thickned Air, giveth a refifiance, caufing it to fwirn in a nimble fluid Body. V (iiicifiiinif if? priiiqifcd shift; ""1"" It is neceffary for Birds upon divers occurrences, to fport themfelves in the Air, and at other times to treat themfelves upon Earth; whereupon they are compofed of folid Bodies, invel'ted with a light hollow Covering, the one to give them Fray and motion above, and the other more pondes rous part, are partly infiituted by Nature to incline Birds downward, as to a Center for their better fubfifiance and repofe; elfe if Birds were whols ly made up of Feathers, they would always flie up and down the Air as reltlt-fs bodies, being not able to have recourfe to land; Whith is effected by their folid bodies, naturally tending downward, and aflilied by fame finall Expafion, and with little or no motion of the Wings, width are fome- what contraé‘tcd in the defcent of Birds to the Ground. . V And it is further requifite for Birds to have Expanded Wings ( to fup- ‘31:}; $11,513:; port them in the Air) afied with various P‘ofiures, in order to pafs from "l"‘i‘nfiupg, 'l'erm to 'lerm, according to fimple motion upward, downward, and di_ 3:25.355; reé'tly forward, and according to oblique and mixed Motions, as bending l'qmy' toward the right, orleft. _ V The motion of Soaring, is performed by molt firong and impetuous Vibrations of the Wings (lifted up'and down by the Scapular, ral Nliillles) upon the Air, thereby fquecfed into a greater and Peritoclofenefs, b whole refiitance, and their Trains being clapped downward, the bodies of Birds are mounted upwards, and on the other fide they are carried downs ward by the Wings giving way to the weight of their Bodies. The motion of Fowls is produced by Extended Wings, making frequent somnggsfau Vibrations ‘ upon the Air, not preffed only directly downward as in Soaring, . _ . {ii-lg the. l" but allo beaten backward, whereupon Birds dart themfelves forward in di~ dusfllydow-g:P I'C& COlll‘fC Ward, and , move Forward And Birds are moved obliquely to the right, when the great firefs of Eiri-lifd"i§.ii. Motion is celebrated by the left Wing, which being more flzrongly Agita: :Effiba‘k‘ ted, the Body by confcquence muft be inclined to the right; and on the Enigma other tide, when the left Wing is favoured, and the right more highly em- my"??? pioyed, the body of Birds doth wheel toward the left in oblique motion writing"; And this may fecm worthy our remark, that in referen ce to fimple and "mg, mixed Nlotion, that the Air is Attenuated in the fore part, and Condenfed in the hinder, by the repeated appulfcs of the Wings, which giveth to the motion backward, and ihooteth Birds forward in flight, with a check the grea- er force. Theciii‘cfrrio'; . I . t' f the And upon enqmry, we may find the dcpreffion of the Expanded Wings vifrilgsois ma‘dc‘ is the moi} eminent in the flight of Birds, and the Elevation is only fubor- 2:33:33? din; te to it, as a prerequiiite condition; when the Shoulder being lifted up, 23;; $32,": the remnant-t: |