Page images
PDF

ment thereof, the Wings. Which as they are prin

cipal Parts, fo are made with great Skill, and placed in the most commodious Point of the Bo

[ocr errors]

tile Medium, the Air. i." - -

And here it is observable, with what incomparable Curiofity, every Feather is made; the Shafi exceeding strong, but hollow below, for Strength and Lightnefs fakes and above, not much lefs strong, and filled with a Parenchyma or, Pitb, both strong and light too. The Vanes as nicely. gauged on each Side as made; broad on one Side, and narrower on the other ; both which incomparably minifter to the progressive. Motion of the Bird, as also to the Union and Clofeness of the Wing (4). , , ,

[ocr errors]
[ocr errors]

(3) In all Birds that dy much, or that have the most occasion for their Wings, it is manifest that their Wings are placed in the very best part, to ballance their Body in the : and to give as swift a ::::: as their Wings and ody are capable of: For oth them to reel, and fly unfleadily ; as we fee them to do, if we alter their Æquipoife, by cutting the end of one of the Wings, or hanging a Weight at any of the extreme parts of the Body. But as for fuch Birds as have as much occafion for Swimming as Flying, and whose Wings are therefore fet a little out of the Center of the Bodies gravi: fee Ch. 3. Note 9. And for such as have, more occafion or Diving than Flying, and whose Legs are for that Reafon fet more backward, and their Wings more forward, fee Ch. 4. Note 9. ( 3 ** -- f - -; (4). The wife Author of Nature hath afforded an Example of the great Nicety in the Formation of Birds, by the Nicety obferved in, a patt no more confiderable than the

Vanes of the Flag-feathers of the Wing. ; Among others,

these two things are observable. , 1. The Edges of the exterior or marrow Vanes bend downwards, but of the interior, wider Vanes upwards ; by which means they catch, hold, and lie close to one another, when the Wing is spread; fo that not one Feather may miss its full Force and Impulse

upon

[ocr errors]
[ocr errors]

And no lefs exquifite is the Textriné Art of the Plumage (5) alfo; which is fo curiously wrought, - - - - and

- · * - - : upon the Air. 2. A yet leffer Nicety is obferved, and that is in the very floping the tips of the Flag-feathers: The interiour Vanes being neatly flopèd away to a Point, towards the outward part of the Wing; änd the exteriour Vanes floped towards the Body, at leaft in many Birds; and in the middle of the Wing, the Vanes being equal, are but little floped. So that the wing, whether extended or shut, is as neatly floped and formed, as if confiantly trimmed with a pair of Sciffors. - - - - (5) Since no exast account that I know of, hath been given of the Mechanism of the Vares or Webs of the Feathers, my Observâtions may not be unacceptable. The Vane confifts not of one continued Membrane, because if óņce broken, it would hardly be , reparable: But of rhanỷ tamine, which are thin, , stiff, and fomewhat of the nature of a thin Quill. Towards the Shaft of the Feather (especially in the Flagfeathers of the Wing), those Laminæ are broad, Ge. of a femicircular Form; which ferve for frength, and for the closer shutting of the Lumine to one another, when İmpulfes are made upon the Air. Towards the outer part of the Vane, these Lamine grow flender and taper: On their under fide they are thin and fmooth, but their upper outer Edge is parted into two hairy Edges, each fide having a different fort of Hairs, laminated or broad at bottom, and flender and bearded -above the other half. I have, as well as I could, represented the uppermoft Edge of one of thefe Laminæ in Fig. 18. with fome of the Hairs of each fide, magnified with a Microscope. Thefe bearded Briffles or Hairs on one fide the Laminæ, have ftrait Beards, as in Fig. 19. : on the other fide, have hooked Beards on one fide the ender part of the Briftle, and ftrait ones on the other, as in Fig zo. Both these forts of Bristles magnified (only frattering and not clofe) are represenged as they grow upon the upper Edge of the Lamina f. t. in Fig. 18. And in the Vane, the hooked Beards of one Lamina, always lie next the ftrait Beards of the next Lamna, and by that means lock and hold each other, and by a pretty Mechanism, brace the Lamine close to one another. And if at a y time the Vane happens to be ruffled and difcomposed, it cặn by this þretty easy Mechanim, be reduced and repaired. V. Book 4. Eh, tz, at Note 12. - - - # (6) and fo artificially interwoven, that it cannot be viewed without Admiration, especially when the Eye is aflifted with Glaffes. And as curiously made, fo no lefs curiously are the Feathers placed in the Wing, exaćtly aceording to their feveral Lengths and Strength: The Principals fet for Stay and Strength, and these again well lined, faced, and guarded with the Covert and Secondary Feathers, to keep the Air from pailing through, whereby the stronger Impulses are made thereupon ' And laftly, to say no more of this Part, that dèferves more to be faid of it, what an admirable Apparatus is there of Bones, very strong, but withal light and incomparably wrought? of foynts, which open, fhut, and every way move, according to the Occasions either of extending it in Flight, or withdrawing the Wing again to the Body ? and of various Muscles; among which the peculiar Strength of the Pestoral "::: deferves especial Remark, by reafon they are much ftronger (6) in Birds, than in Man, or any other Animal, not made for Flying. : ? ; 4: Next the Wings, the Tail is in Flight confiderable; greatly allifting in all Ascents and De: - - - : ': *** · · · · · · · · - fcents | * '::- , * - * , ! A --— - - } - " . (6) Pečiorales Musculi Homiris fiełłemes húmeros, parti & parum carnofi funt; non æquant foam aut 7cam partem omnium Musculorum Hominis. E contra in Avibus, Festorales Musculi vafiffimi funt, & æquant, imo excedunt; & magis pendent, quam reliqui omnes Musculi ejusdem Avis fimul fumții. Borell de Mot. Animal. Vol. I.Prop. 184 , Mr. Willughby having mede the like Observation, hath this Re feoion on it, whence, if it te possible for Man to fly, it is thought by them who have curiously weighed and confidered the mariér, that be that would attempt fuch a thing with hopes of success, muft fi contrive and adapt his Wing, that he may make use of his Legs, and not bis Arms in managing them ; (because the Muscles of the Legs are stronger, as he observes.) Willugh, ornith. k. 1, c. i. s. ". :) - |- 7

[ocr errors]

ents in the Air; : as also ferving to steady (7) Flight, by keeping the Body upright in that fubtile and yielding Medium,, by its readily : and ::::: every Vacíllation of the body. . . . . . . . . . . . . . . · · · And now to the Parts ferving to Flight, let us add the niçe, and compleat. Männer of its Performances, allt doile according to thed strictest Rules of Mechanifm. (8) . What Rower on the Waters, what Artist on the Land, what acuteft Mathematician could give a more agreeable and exact Motion to the Wings, than thefe untaught flying Artists do theirs! ferving not only to bear their Bodies up in the Air, but also to waft them along therein, with a speedy progreffive Motion, as also to fteer and turn them this Way and that Way, up and down, fafter or flower, as their Occafions require, or their Pleasure leads them. 5. Next to the Parts for Flight, let us view the Feet and Legs, miniftering to their other Motion; Both made light, for eafier Transportation through the Air; and the former fpread, fome with Membranes for Swimming (9), fome vi: - - - - - or

(7) Mr. Willuzhby, Ry, and many others, imaginé ths

principal ufe of the Táil to be to steer, and turn the Bod in the Air, as a Rudder. : Borelli hath put it beyond al doubt... that this is the leạft u e of it, and that it is chieflý to affift the Bird in its Afcents and Descents in the Air, and to obviate the Vacillations of the Body and Wings. , For as for turning to this or thit fi le, it is perfo med by the Wings, and Inclination of the Body, and but very little by the help of the Tail. - - (8) See Borelli ubi fupr: Prop. 182, Gr. |- č9ð It is confiderable in all water-Fowl, how exactly their Legs and Feet correspond to that way of Life. For either their Legs are long, to enable them to wade in the waters: In which cafe, their Legs áre bate of Feathers a ġood way above the Knees, ;: miợre čønttä:Ently for :: # rra

for fteady Going, for Perching, for Catching and Holding of Přey (Io), or for Hanging by the Heels to gather their Food (11), or to fix theinfelves in their places of Retreat and Safety. And the latter, namely the Legs, all curved for their eafy Perching, Roofting, and Reft, as also to help them upon their Wings in taking their Flight, and to be therein commodiously tucked up to the Body, fo as not to obstruct their Flight. In fome long, for Wading and Searching the Waters; in fòme of a moderate Length, anfwerable to, their vulgar Occasions; and in others as remarkably fhort, to anfwer their efpecial Occasions and Manner of Life (12). To all which let us add the

[ocr errors]
« PreviousContinue »