University of Wisconsin Digital Collections
Link to University of Wisconsin Digital Collections
Link to University of Wisconsin Digital Collections
History of Science and Technology

Page View

Hooke, Robert, 1635-1703 / Micrographia: or some physiological descriptions of minute bodies made by magnifying glasses : with observations and inquiries thereupon
(MDCLXVII [1667])

Observ. XXXIX. Of the eyes and head of a grey drone-fly, and of several other creatures,   pp. 175-180

Page 177

               M ICROGRAPHI A.
yet obferv'd them rang'd in a quadrangular order, the rows cutting each
other at right angleswhich as it admits of a lefs number of Pearls in equal
furfaces; 16o have thofe creatures a recompence made them, by having
their eyes a little movable in their heads, which the other altogether
want. So infinitely wife and provident do we find all the Difpenfations in
Nature, that certainly Epicuros, and his followers, muft very little have
confider'd them, who akcrib'd thofe things to the produdion ofchance,
that willto a more attentive confidererappear the produtts of the higheft
Wifdom and Providence.
     Upon the Anatomy or Difke&ion of the Head, I obferv'd thefe par-
  Firft, that this outward fkin, like the cornea of the eyes of the greater
Animals, was both flexible and tranfparent, and feem'd, through the &i-
crofcope, perfectly to refemble the very fubftance of the cornea ofa man's
eye; for having cut out the clufter, and remov'd the dark and mucor
ftuff that is fubjacent to it, I could fee it transparent like a thin piece
(kin, having as many cavities in the infide of it, and rang'd in the fame
order as it had protuberances on the outfideand this proprietyl found the
fame in all the Animals that had it, whether Flies or Shell-Fifl.
  Secondly, I found that all Animals that I have obferv'd with thofe kind
of eyes, have within this cornea, a certain cleer liquor or juice, though
a very little quantity, and,
  I obferv'd thirdly, that within that deer liquor, they had a kind of
dark Nnucom lining, which was all fpread round within the cavity ofthe
clufter, and feem'd very neer adjoining to it, the colour of which, in
fome Flieswas grey 5 in others, black; in others red; in othersof a mix'd
colour; in othersfpotted; and that the whole clufters, when look'd on
whilff the Animal was living, or but newly kill'd, appear'd of the fame
colour that this coat (as I may fo call it) appear'd of, when that outward
fkin, or Cornea,was remov'd.
  Fourthly, that the reft of the capacity of the clufters was in fome, as
in Dragon Flies, &c. hollow, or empty 5 in others fill'd with fome kind
of fubftance ; in blue Flies,with a reddifh mufeulous fubftance, withfires
tending from the center or bottom outwards; and divers other,with va-
rious and differing kinds offubftances.
  That this curious contrivance is the organ of fight to all thofe various
Cr4flaceous Animals, which are furnifh'd with it, I think we need not
doubt, if we confider but the feveral congruities it has with the eyes of
greater creatures.
   As firft, that it is furnifh'd with a Corneawith a transparent hbmour,and
with a uvea or retina, that the Figure of each of the fmall Hfem4ifheres
very Spherical, exactly polifh'd, and moft vivid, lively and plump,when
the Animal is living,as in greater Animals,and in like manner dull,flaccid,
and irregular, or flrunk,when the Animal is dead.
   Next, that thofe creatures that are fiirnifh'd with it, have no
other organs that have any refemblance to the known eyes of other
B b

Go up to Top of Page