Of Feathers, 3 7 
admirably wove together, as to refill the air; and are 
fo extreamly fmall, that the 500th part of an inch 
exceeds them in thicknefs. 
The parts of the feathers of a peacock, appear through 
the microfcope no lefs beautiful than the whole feather 
does to the naked eye ; the Item of each feather in the 
tail, fends out multitudes of lateral branches ; fuch as 
A B, of fig. 73. which reprefents one thirty fecond-part 
of an inch, each of thefe lateral branches emits num¬ 
bers of little fprigs or hairs, on each fide, as C D, C D, 
C D, each of which in the microfcope appear to con- 
fid of a multitude of bright fliining parts, which are a 
congeries of fmall plates, as e, e, e, e, e, &c, each fhaped 
like a, b, c, d, of fig. 74. ac being a prominency or 
item ; and d and b the corners of two fmall thin plates, 
that grow into the fmall dalk in the middle, making a 
kind of little feather, and lie clofe to, or rather upon 
each other in the manner of tiling; they grow on each 
fide of the {talk, oppofite to each other, by two and 
two, in the manner expreffed by fig. 75. the tops of 
the lower ones covering the roots of thofe next above 
them; the under fides of each of thefe plates are very 
dark and opake, reflecting all the rays call upon them ; 
much like the foil of a looking-glafs; but their upper 
fides feem to confift of a multitude of exceedingly thin 
plated bodies, lying clofe together, and thereby like 
mother of pearl (hells do not only reflect a very brifk 
light, but even tinge that light fo reflected in a mod 
curious manner, which by various pofitions of the light, 
reflect fird one colour and then another, in a mod vivid 
apd furprizing manner. And that thefe colours arife 
only from the refraction of light, he found that wetting 
tfie colour’d parts with water, dedroyed their colours, 
and though he was not able to fee thofe hairs at all 
P 3 trandarerd 
