168 
MicROGRAPHDAs 
tude of bright reflecting parts, whofe Figure tis no eafie matter to de 
termine, ashe that examinesit fhall find; tor every new pofition of it to 
the light makes it perfectly feemofanother form and fhape,and nothing 
what. it) appear'd -avlittle: before; nay, it appear'd very differing oft: 
times from bE feemingly inconfiderable a circumftance, ‘that:the iter: 
pofing of oneshand’between the light and it,makes a very great change, 
andthe opening or fhutting a‘Cafement and the like, very much :diverfi: 
fiesthe appearance. “And though, by examining the form of it very many 
ways; which would-be tedious here to enumerate, I fuppofe I have dif 
cover'd the true Figure of it, yet oftentimes, upon looking on it inano- 
ther: pofture, ‘I have almoft thought my former obfervations deficient, 
though indeed, upon further examination, I have found even thofealfo 
to confirmthem, (001 lon sol oe to 
Thefe threads therefore I find to be a congeries of {mall Lamine or 
platesy: as elee e e, &c. each of them fhap'd much like this of 4 bed, in 
 thefourth Figure,the’part 2c being a ridge, prominency, orftem, and 
| 2and d the corners of two {mall thin Plates that grow unto the fmall 
| ftalk in the:middle:fo that they make a kind of little feather; eachiof thefe 
Plates liecne clofe to another,almoft like a company of floping ridge or 
utter Tyles; they gow! on each fide of the {talk oppofite to one another, 
yi two! and two, from top to bottom; in the manner exprefs‘d in the 
fitth Figure, the tops of the lower covering the roots of the next above 
thems the under fide ‘of each of thefe laminated bodies, is ofa very dark 
and opacous {ubftance, and fuffers very few. Rays to be trajeéted, but re- 
flects them all toward that fide from whence they come, much like the 
foil of a Looking-glafs; but their upper fides feem to me to confift of 
| a multitude of thin plated bodies, which are exceeding thin, and lie ve-_ 
\ ry clofe together, and thereby, like mother of Pearl fhells, do not one- 
_ dy reflect a very brifk light, but tinge that light in'a moft curious man- 
ner; and by means of various pofitions, in refpect of the light, they re- 
3; back now one colour, and then another, . and thofe moft vi- 
vidly. Sheer 
Now, that thefe colours are onely faxtaftical ones, that is, fuch as arile 
) immediately from the refractions of the light, I found by this, that-water 
' wetting thefe colour‘d parts,deftroy’d their colours,which feem’d to pro- 
ceed from the alteration of the reflection and refraction. Now, though 
I was not able to fee thofe hairs at all tranfparent by a.;common light, yet 
by looking on them againft the Sun, I found them ‘to be ting’d wih a 
darkifh red colour, nothing a-kin to the curious and lovely and 
blues they exhibited. | asd od i 
What the:reafon of colour feenis to be in fuch thin plated bodies, I 
have elfewhere fhewn. But how water caft upon thofe threads deftroys 
their colours, I {uppofe to be perform’d thus; The water perez 
thefe plated bodies from its having a greater congr ity to Featherst 
the Atr,infinuates it {elf between the Platesanth Ge extrudes the ftrong 
reflecting Air, whence both thefe parts grow more tranfparent,as the 24- 
erofcepe informs, and colourlefs alfo, at beft retaining a very faintand 
ak he one 
rg 
em 
” 
