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النشر الإلكتروني

APRIL.

SOLAR PHENOMENA.

I see, diffused

In radiant orders, essences sublime,
Of various offices, of various plume,

In heavenly liveries distinctly clad,

Azure, green, purple, pearl, or downy gold,

Or all commixed; they stand, with wings outspread,
Listening to catch the Master's least command,

And fly through nature ere the moment ends.

Light and Colors. If the objects of the material world had been illuminated with white light, all the particles of which possessed the same degree of refrangibility, and were equally acted upon by the bodies on which they fall, all nature would have shone with a leaden hue, and all the combinations of external objects, and all the features of the human countenance, would have exhibited no other variety but that which they possess in a pencil sketch or a China-ink drawing. The rain-bow itself would have dwindled into a narrow arch of white light,—the stars would have shone through a grey sky,—and the mantle of a wintry twilight would have replaced the golden vesture of the rising and the setting sun. But he who has exhibited such matchless

skill in the organization of material bodies, and such exquisite taste in the forms upon which they are modelled, has superadded that ethereal beauty which enhances their more permanent qualities, and presents them to us in the every varying colors of the spectrum. Without this the foliage of vegetable life might have filled the eye and fostered the fruit which it veils,— but the youthful green of its spring would have been blended with the dying yellow of its autumn. Without this the diamond might have displayed to science the beauty of its forms, and yielded to the arts its adamantine virtues ;-but it would have ceased to shine in the chaplet of beauty, and to sparkle in the diadem of princes. Without this the human countenance might have expressed all the sympathies of the heart, but the "purple light of love" would not have risen on the cheek, nor the hectic flush been the herald of its decay.

The gay coloring with which the Almighty has decked the pale marble of nature, is not the result of any quality inherent in the colored body, or in the particles by which it may be tinged, but is merely a property of the light in which they happen to be placed. Newton was the first person who placed this great truth in the clearest evidence. He found that all bodies, whatever were their peculiar colors, exhibited these colors only in white light. When they were illuminated by homogeneous red light, they appeared red; by homogeneous yellow light, yellow, and so on; "their colors being most brisk and vivid under the influence of their own day-light colors." The leaf of a plant, for example, appeared green in the white light of day, because it had the property of reflecting that light in greater abundance than any other.

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When it was placed in homogeneous red light, it could no longer appear green, because there was no green light to reflect; but it reflected a portion of red light, because there was some red in the compound green which it had the property of reflecting. Had the leaf originally reflected a pure homogeneous green, unmixed with red, and reflected no white light from its outer surface, it would have appeared quite black in pure homogeneous red light, as this light does not contain a single ray which the leaf was capable of reflecting. Hence the colors of material bodies are owing to the property which they possess of stopping certain rays of white light, while they reflect or transmit to the eye the rest of the rays of which white light is composed.

So far the Newtonian doctrine of colors is capable of rigid demonstration; but its author was not content with carrying it thus far,—he sought to determine the manner in which particular rays are stopped, while others are reflected or transmitted; and the result of this profound enquiry was his theory of the colors of natural bodies.-Brewster's Life of Newton.

Thomson, the author of the Seasons, in his poem, sacred to the memory of Sir Isaac Newton, thus refers to the discoveries of this great philosopher in this beautiful branch of science: :

Nor could the darting beam of speed immense
Escape his swift pursuit, and measuring eye.
Even light itself, which every thing displays,
Shone undiscovered, till his brighter mind
Untwisted all the shining robe of day;
And from the whitening undistinguished blaze,
Collecting every ray into his kind,

To the charmed eye educed the gorgeous train,

Of parent-colors. First the flaming red
Sprung vivid forth; the tawny orange next;
And next delicious yellow, by whose side
Fell the kind beams of all-refreshing green.
Then the pure blue, that swells autumnal skies,
Ethereal played; and then of sadder hue,
Emerged the deepened indigo, as when
The heavy-skirted evening droops with frost.
While the last gleamings of refracted light
Dyed in the fainting violet away.

These, when the clouds distil the rosy shower,
Shine out distinct adown the watery bow;
While o'er our heads, the dewy vision bends
Delightful, melting on the fields beneath.
Myriads of mingling dyes from these result,
And myriads still remain; infinite source
Of beauty, ever-blushing, ever-new!

The sun enters Taurus at 36 minutes after 2 of the morning of the 20th of this month.

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Conjunctions of the Moon with the Planets and Stars.

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The conjunction of the Moon with Saturn will prove an occultation.

PHENOMENA PLANETARUM.

Mercury, in perihelion, on the 2nd of this month, attains his greatest north latitude on the 13th. At his greatest elongation, as an evening star, on the 14th, angle of elongation, 19° 50′. Stationary on the 24th, near in Aries.

Venus in conjunction with Jupiter at 11 of the night of the 3rd, difference in declination, 19'; with in Aquarius on the 4th, difference of latitude, 15'. In aphelion on the 9th.

Phases of Venus.

The proportions of the bright and dark phases of this planet are as follow:

April 1st.-Illuminated part = 10.3075

Dark part...... = 1.6925

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Mars in conjunction with in Capricornus on the 3rd, difference of latitude, 7'; with 54 in Aquarius on the 25th, difference of latitude, 11'.

The Asteroids.

Hrs. Min.

Vesta, 2nd day. Right Ascension, 8 15 N. Declin. 25° 49'

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