Birds and All Nature, Vol. 4, No. 3, September 1898: Illustrated by Color PhotographyVarious
History
Birds and All Nature, Vol. 4, No. 3, September 1898: Illustrated by Color Photography
Various
Birds -- Periodicals; Natural history -- Periodicals
Mr. Murdock says the birds breed in abundance at Point Barrow, Alaska,
and that the nest is always built in the grass, with a preference for
high and dry localities. The nest was like that of the other waders, a
depression in the ground, lined with a little dry grass. The eggs are
four, of pale purplish-gray and light neutral tint. It is sometimes
called Grass Snipe.
[Illustration: From col. Chi. Acad. Sciences.
PECTORAL SANDPIPER.
1/2 Life-size.
Copyright by
Nature Study Pub. Co., 1898, Chicago.]
EYES.
By W. E. WATT.
Why was the sight
To such a tender ball as th' eye confined,
So obvious and so easy to be quenched,
And not, as feeling, through all parts diffused;
That she might look at will through every pore?--MILTON.
"But bein' only eyes, you see, my wision's limited."--SAM WELLER.
The reason we know anything at all is that various forms of vibration
are capable of affecting our organs of sense. These agitate the brain,
the mind perceives, and from perception arise the higher forms of
thought. Perhaps the most important of the senses is sight. It ranges
in power from the mere ability to perceive the difference between light
and darkness up to a marvelous means of knowing the nature of objects
of various forms and sizes, at both near and remote range.
One the simplest forms of eyes is found in the Sea-anemone. It has a
colored mass of pigment cells and refractive bodies that break up the
light which falls upon them, and it is able to know day and night.
An examination of this simple organ leads one to think the scientist
not far wrong who claimed that the eye is a development from what was
once merely a particular sore spot that was sensitive to the action
of light. The protophyte, _Euglena varidis_, has what seems to be the
least complicated of all sense organs in the transparent spot in the
front of its body.
We know that rays of light have power to alter the color of certain
substances. The retina of the eye is changed in color by exposure to
continued rays of light. Frogs in whose eyes the color of the retina
has apparently been all changed by sunshine are still able to take a
fly accurately and to recognize certain colors.
Whether the changes produced by light upon the retina are all chemical
or all physical or partly both remains open to discussion.
Public-domain text, read in full here on John Shaqi.
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