| MicrocRaPHias’ 
dull colour. But this wet being wafted away by the coptinial evapona- 
_-tionsand {teams that pafs through them from the Peacock; whil ft that 
Bird is yet alive, the colours again appear in their former Juftenpthe.z 
terfistia of thefe Plates being fill'd with the ftrongly refledting Air, 40 
The beauteous and vivid colours ofthe Feathers of this Bird; bei 
found to proceed from the curious and exceéding fmalnef and:finen 
of the refieCting parts,we have here the. reafon given 1is:of all: thofegaut 
deries inthe apparel of other Birds alfo,: and-how'they icome to exceed 
the colours of all other kinds of Animals, befidesImfectss forfince (as we 
here,and ¢lfewhere alle thew) the vividneds of :aldolour, depends upon 
the finenefs and tran{parency of the seflectingand-reftading parts} and 
fince our AGcrofc ope difcovers to us; that the component patts of feathers 
are fuch, and that the hairs of Animals are otherwife3 and fince!we find 
alfo by the Experiment of that Nobleand moft Excellent Perfon Lforiner+ 
lynamed; that the dificrence between Silkand Flax} as touits cdldur, is 
nothing ¢lfe (for Flax reduc’d to a very’ great finenefs' of parts; “both 
white and colour'd, appears as whice‘and as vividias any Silk, but lofes 
that brightnefs and its Silken afpe@ as foon as it is twilted into thread,by 
reafon that the component parts, though very {mall and fine, are yet alk 
able flakes, and not cylinders, and thence,by twifting, become uhited in- 
toone opacous body, whereas the threads of Silk and. Feathers tetain 
their luftre, by preferving their cylindrical form: intire without mix- 
ing; fo that each refietted and refratted beam that compofes: the glo& 
of Silk, preferves its own property of modulating the light intire)3 And 
fince we find the fame confirm’d by many Fe er 2a where 
mentioned, I think we may fafely conclude this for an Axidme;'that 
wherefoever we mect,with tran{parent bodies, fpun.out into very fine 
parts, either cleer, or any ways ting’d, the colours refulting ffom {uch a 
‘compofition. muit neceflarily be very glorious, vivid, and cleer} like thofe 
of Silk and Feathers. This may perhaps hint fome ufefull way of making | 
other bodies, befides Silk, be fufcéptible of bright tinétures, but of this | 
onely by the by. j 70 Aig pbaeie mones sis mor 
The changeable colour'd Feathers alfo of Ducks, and {everal: other 
Birds, Ihave found by examination with my AGerofcope, to procced from 
much the fame caufesand textures. ©. ice 
Pe 
‘teen 
Obfery, KXXVII. Of the Feet of Flies, and feveral otber Ine 
fetts, Be ee ey bre -boicid 
a foot of a Fly (delineated in the firlt Figure of the 23. Scheme, 
hee © aeicrboiieietcires joints, the two Tallons, and the two Pattens 
ina flat pofture ; andinthe fecond Figre of the fame Scheme, whithre- 
prefents onely one joint, the Tallons and Pattehs in another pofture) 1s 
of a moft admirable and curious contrivance, for by this the Flies are in- 
abled to walk apaintt the fides of Glafs, pei? upwards, and to 
nh hed 
r 
; Se 
contain 
’ 
i 
i 
} 
469 
