DOI Page / Citation link:
https://doi.org/10.11588/diglit.68888#0262
Observ. X X X1 X. Of the Eyes and Head of a Grey drone* Fly,
and ofsever al other creatures.
I took a large grey Drone-Fly that had a large head, but a small and
llender body in proportion to it,and cutting oss its head, I fix’d it with
the forepart or face upwards upon my Objest Plate (this I made choice
of rather then the head ofa great blue Fly,because my enquiry being now
about the eyes,I found this Fly to have, in st the biggest clutters of eyes
in proportion to his head, of any (mail kind of Fly that I have yet seen, it
being somewhat inclining towards the make os the large Dragon-Flies.
Next, becaule there is a greater variety in the knobs or balls of each
clutter,then is of any sinal] Fly) Then examining it according to my ulual
manner, by varying the degrees of light, and altering its petition to each
kinde of light, I drew that representation of it which is delineated in
the 24. Scheme., and found these things to be as plain and evident, as
notable and pleasant.
Firfii that t'he greatest part of the face,nay,of the head,was nothing elfe
but two large and protuberant bunches,or/r0»fr»r»tparts,A B C D E A,the
surface of each of which was all cover’d over, or shap’d into a multitude
of sinall Hemijpheres^plac’d in a triagonal 01'der,that being the closest and
most compacted, and in that order, rang’d over the whole lurfaceof the
eye in very lovely rows,between each of which, as is necessary, were left
long and regular trenches, the bottoms of every of which, were perfectly
intire and not at all perforated or drill’d through, which I most certainly
was allured of, by the regularly refiested Image of certain Objects which
I mov’d to and fro between the head and the light. And by examining
the Cornea or outward Ikin, after I had stript it off from the ieveral sub-
stances that lay within it,and by looking both upon the inside and against
the light.
Next, that of thole multitudes of Hemijpheres, there were oblervable
two degrees of bigness, the half of them that were lowermost,and look’d
toward the ground or their own leggs, namely, CDE, CDE being a
pretty deal smaller then the other, namely, A B C E, A B C E, that look’d
upward, and side-ways,or foreright,and backward, which variety I have
not found in any other sinall Fly.
Thirdly, that every one of thele Hemijpheres.ps they seem’d to be pret»
ty neer the true lhape of a Hemisphere, so was the lurface exceeding
smooth and regular, ressesting as exast, regular, and perfest an Image of
any Objest from the surface of them, as a small Ball of Quick-silver os
that bignels would do, but nothing neer so vivid, the ressestion from thele
being very languid, much like the ressestion from the outside of Water,
Glass. Crystal, &e. In lb much that in each of thele Hemispheres, I have
been able to difcover a Land-lcape of those things which lay before my
window^
and ofsever al other creatures.
I took a large grey Drone-Fly that had a large head, but a small and
llender body in proportion to it,and cutting oss its head, I fix’d it with
the forepart or face upwards upon my Objest Plate (this I made choice
of rather then the head ofa great blue Fly,because my enquiry being now
about the eyes,I found this Fly to have, in st the biggest clutters of eyes
in proportion to his head, of any (mail kind of Fly that I have yet seen, it
being somewhat inclining towards the make os the large Dragon-Flies.
Next, becaule there is a greater variety in the knobs or balls of each
clutter,then is of any sinal] Fly) Then examining it according to my ulual
manner, by varying the degrees of light, and altering its petition to each
kinde of light, I drew that representation of it which is delineated in
the 24. Scheme., and found these things to be as plain and evident, as
notable and pleasant.
Firfii that t'he greatest part of the face,nay,of the head,was nothing elfe
but two large and protuberant bunches,or/r0»fr»r»tparts,A B C D E A,the
surface of each of which was all cover’d over, or shap’d into a multitude
of sinall Hemijpheres^plac’d in a triagonal 01'der,that being the closest and
most compacted, and in that order, rang’d over the whole lurfaceof the
eye in very lovely rows,between each of which, as is necessary, were left
long and regular trenches, the bottoms of every of which, were perfectly
intire and not at all perforated or drill’d through, which I most certainly
was allured of, by the regularly refiested Image of certain Objects which
I mov’d to and fro between the head and the light. And by examining
the Cornea or outward Ikin, after I had stript it off from the ieveral sub-
stances that lay within it,and by looking both upon the inside and against
the light.
Next, that of thole multitudes of Hemijpheres, there were oblervable
two degrees of bigness, the half of them that were lowermost,and look’d
toward the ground or their own leggs, namely, CDE, CDE being a
pretty deal smaller then the other, namely, A B C E, A B C E, that look’d
upward, and side-ways,or foreright,and backward, which variety I have
not found in any other sinall Fly.
Thirdly, that every one of thele Hemijpheres.ps they seem’d to be pret»
ty neer the true lhape of a Hemisphere, so was the lurface exceeding
smooth and regular, ressesting as exast, regular, and perfest an Image of
any Objest from the surface of them, as a small Ball of Quick-silver os
that bignels would do, but nothing neer so vivid, the ressestion from thele
being very languid, much like the ressestion from the outside of Water,
Glass. Crystal, &e. In lb much that in each of thele Hemispheres, I have
been able to difcover a Land-lcape of those things which lay before my
window^