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Show Isms «More w-v-r . 0f the Ftarberr of Birds. In Convex luti'acc of the Stciiim. Th: Concave inriace ot'the Stemm. The upper Nnigent of the \(k'mnl. The inl'uioi‘ Margerri The oblong b: mad tildments. Book!" The Stein is dothed with a Convex-furlace in its upper Region,and "id, 2 Concave in its lower, through which a Filliire palleth all along from it, Bafe to the Cone, dividing the inferior part of the Stem into equal Parts. The upper Margents ofcach fide ofthe Stem, adJOYHIllg to the Concavta. furface, are befet with Two ranks of Filaments, or Hairs, the higher are lliort and fmall, andthe inferior fomewhat larger and longer, and are b011, inferted in their Origens into the horny covering of the Stern Thcfc oblong broad Filaments have their Origens larger, and end into Cones; they are placed in great order, and for the molt part nearly conjuyn. ed to each other by a glutinous Matter; and if they be rendted fometvhac difordred by violent motion ofthe wings in a great flight, they are eafily re‘ duced into order, as drawn between the upper and lower Beaks of Birds. The Friiigcsof tlicjstcmm. The Stein is not only beautified on each lide with curious Fringes, fta. med of many fine downy Hairs, dil'tinguilhed with numerous creces as f0 Imny partitions,but is rendred firong with a thin horney covering (incirclinga White, Coagulated, Spungy Subl'tance, making the Cavity of the Stem full and tight 5 fothat it cannot be ealily bent, when the Feathers are moved with great force in the flying of Birds. And this white curdly Matter(llul'ling up the hollownefs ofthe Stein) con. duéteth the tender \/ellels, in order to the nutrition of the neighbouring parts; , t The various Colon rs of Fathers. 0f the Feat/Jeri- of fBim'r. [award another is reflet‘led, ( as fuffeting various Refraéiions) through the Interl'tices of the Plates,filled with Air, acted with beams of Light,lo that the fine fpun Filaments of Feathers, adorned with bright refleéting Particles, muli needs produce variety of glorious lively colours, as the rays of Light f on themfelves in feveral pollUtes in the Interl'tices of the flakes of Feailiets interfpetfed with the elal'tick Particles of Air. This gay Apparel of Feathers, as died with variety of pleafant Colours, is not intended by Nature f0 much for Ornament as Ufe, which is to invell the tender Skin, to fecure it againl't the importunate blalts of cold wea- Birds light, in order to flying, to give the greater advantage to the elallzick Particles of Air, to fupport their weight, and transfer them from place to Place; which is accomplilhed by a Mechanifme of the wings ( contrived by nature with wonderful Artifice) as Machines of Flying, and are framed of many articulated bones, of the Scapula, Humerm, Cubite, Radix", and Car. pm , curioully difpofed into Joynts, which being enwrapped one with in another, by Mufcles called Flcxorr, do bring the wing into a fmall Model, and make it fit clofe to the Body, to give cafe to Birds in their re, pole and freedom from flying. and I humbly conceive, that thefe white, Spungy Particles, ferve alfo as lo The wing is firetched and expanded by the Tenfors, unfolding the fevetal bones ofthe Pinion, and do fit it for flying, which is performed partly by of Colours, which I humbly conceive are rather imaginary and apparent; then real and inherent, as being f0 many different models of l ight, as it is And other times variety of colours are generated by a number of bright refleéting parts, which accompany minute Bodies ( difpofed in various Poli- tions) whofe Figure it is difficult to allign, by reafon every new pollute, made againl'c the Light, feemeth to give thefe fine reflecting parts a different form, which is very pleafant to behold in a Microfcope. Variety of Colours alfo do owe their Origen to lirong, and fainter AppUlfes of Light, made by oblique Rays, receiving different imprelllons by various Refrafiions, in the ftirfaces of diverfe tranfparent Mediums, affected with feveral degrees of Denfity or rarity 3 whereupon greater or lefs refractions of Light are made, when the Rays are more or Iefs ealily tranfmitted through diverfe thin diaphanous Bodies. The Feathers adorning the Wings and Tails ofBirds, are made up ofmany broad thin Filaments ( feated two by two over againl't each other, as iiiferted into the higher Region of the horny Integument ) and are Syflems 0f innumerable thin Downy Flakes, conjoyned to each other; and the lower Region of thefe laminated Bodies, have a dark fubl‘tance, not receptive 0 Light, bur rel-leéls its Rays to that lide from whence they cotne, and feem much to refemble the foilof a Looking-Glafs; but their upper to be made up of a number of fine Feathers, as f0 many fides 2131"?" plated 1305""! which are very thin, and lye very near together, like the Shells of Mother of Pearl ( as ingenious Mr. Hook hath obfervcd ) which do not only tellea a very brisk Light, but tinge it alfo with divers fine Models, and by V'ari' ous politions, in reference to the Light, now and then one colour, and after- war The fitll lift of Feathers. Second ‘thhe Second and more principal ufe of Feathers, is to render the Bodies of The Life. many Glands to percolate the ferous Liquor of the Blood from the Red Crallament, in reference to the nourilhment of the various parts belonging to the Stemm. The Feathers of feveral forts of Birds areas it were painted with variety fometiinc more or leis deepned by greater or lefs lhadows, produced by a company of diverfe unevennelfes, lituated in the furfaces of Bodies. The pruduéli‘ on ofColoLirs iii Feathers. m1. the Elevators, or Abductors, lifting up the Wing after it is extended, and thief-1y by the Deprelfors, or Addut‘iors, the pectoral Mufcles drawing it downwards, to give a brisk appulfe upon the ambient Air, conlilhngofelaflick Particles, which being comprelfed, do relil't the motion of the Wing. . Birds being more ponderous then the Air, are fupported by the aid of their The Wing is extended and expanded by Tcnfors. Birds are {upyorttd by Air. extended and dilated wings, faltened to the bones of the Stapula, and Hume- rm, feared in the upper region of the body of Birds; whence it may be reafonably inferred, that the center of Gravity is lodged in the lower part , of the Breal't (before the Otigens of the wings) wherein all parts of the bo- dy are equally poyfed or ballanced in a right perpendicular line, palling to the Horizon, from the roots of the wings to the Cavrty of the Abdomen, and middle of the bone of the Breal't, with reference to the length of the Body, in which pollute Birds make their Nells hanging upon the branches of Trees. The Bodiel ofBirds are equally poi!ed. The bodies ofBirds hang in the Air according to an equal ballance of all parts, through whofe middle 3 right line being drawn perpendicularly to the Horizon, is called the Center of Gravity, in which pollute Birds being placed in a fluid Medium, kept from falling downward, as boyed up by alight Compage of Feathers, drcfling the Body and wings of Birds, being expanded, which are firli: lifted up by the Mufcles, called Elevators, and afterward impetuoully drawn downward by the pectoral Mufcles; whereupon the dilated wings do make firong appulfes upon the Air, not in one part, but according to the dimenlions of breadth and length of the whole wmgs,whofe firokesatemade accordina to circular circumferences, agreeing in proporti. my and arife from the Ce‘hter to the Extremity of the wing, whofe appulfes are encountred by the Concave-Surface of the Air, briskly fanned into a thicknefs, and re-aéting ( as Comprelled by the lltokes of the wings) and darting the light Compage of Birds forward, as the elafiick Particles of_Air do lh'ongly prel's upon the under and hinder Region of the body of Birds, Pufliing them forward in flight, as their GraVity is countermanded by a firong refiltence of the afiiVe, expanlivc Particles of Air. K it I ‘ To The Center of Gravity. The various motions of the Wings of Birds. |