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cardboard), then entered the value and color of the sky as 30 bv, and the cloud edges which were higher and silvery. The cloud itself, of varying thicknesses, was warmer in tone than the sky and played, I estimated, between 30 and 40. The moon was about the same value and much grayer than the sky. I was not conscious of any considerable variations of value in the moon and failed to put in the value line. The blackishness of the moon and the center lighter than the edges were undoubtedly optical illusions. Next a quick outline of the corona was made, most attention being paid to the larger rays. Then the binoculars (which had been previously adjusted and focused) were used. Two splendid prominences, slightly pinker and lighter than I had expected, appeared-one near the top of the sun
The artist's original drawing as amended later by reference to photographs made of the corona. The details of the polar rays and of the prominences had been left for the cameras to record. Careful drawings of these features and of the variations in shading of the corona resulted in this composite picture on which was based the painting of the corona (see plate opposite page 245). The lines outlining the corona in this figure may be regarded as contours of luminosity, showing the range and extent of certain degrees of brilliancy around the disk
and the other on the left side below the horizontal. I gave these the highest value which I then thought could be produced by mixing oil paints, viz., 60r. A rose-colored glow stretched along the lower right side of the limb, the value of which was first recorded on the chart as 50.
I recorded two lines of values for the outer corona. I saw no distinct separation of the inner and outer coronas. On the upper left extension greenish and yellowish tones were recorded. No time was wasted on tones thought to be correct in the sample picture. On the whole the corona was less blue than my sample and it retained brilliancy farther out than I expected. Had it been seen against the blue sky it probably would have extended still farther and its disappear
ance might have been more gradual. Two sections of the so-called inner corona were very brilliant, although of course not as high in value as the prominences. These were next to the limb and were very neutral as to color. I outlined them and marked them "whitish," but got one of them in the wrong place. This brought my eyes to the picture for several seconds. About the ninety-fifth second I looked up and was surprised to see that the pink glow had lengthened out and risen in value. This change was due to the motion of the moon, which had by that time uncovered a magnificent solar eruption, but I had no time to take up the glasses. I outlined this glow, its value fully up to 60, which I entered afterward. Figure 2 is a reproduction of the original drawing.
Toward the end I re-outlined the corona, indicating rapidly the polar rays, for the accurate drawing of which, as well as for that of the promi
A graphic representation of the scale of brightness values of the various colors found in the eclipse phenomena.-Varnished ivory black is taken as zero and the best white lead (silver white) as 100 for the points of reference. The most brilliant shades were found in the prominences which consist for the most part of incandescent hydrogen gas with a color approaching that of the red hydrogen line of the spe rum. By careful painting the brightness of the reds used in portraying the prominences was forced up to 67, and a very fiery quality given to them. The brightness of the sky was pitched at 25, as was the moon, while it was estimated that the clouds ranged from 30 to 40, and the corona from about 30 to 60
PAINTING THE SOLAR CORONA
outside edges of the corona were affected.
On the tenth the photographic negatives were shown to me. Those of the sixty-five-foot camera were seven and three eighths inches in diameter, the others considerably smaller. I now saw, in minute detail, the two prominences which I had recorded and the mighty cyclone which had been increasingly revealed as the eclipse neared its end, because of the direction of the moon's motion. We are told that this group of prominences was forty-six thousand miles high. There were many other minor prominences.
I now made careful drawings of these prominences from the negatives and of the variations in shading of the surrounding corona. Many arches were found springing over the prominences, and a few rifts or dark channels radiating from the limb but never coming very close to it. The negatives showed very clearly the hairy polar rays, not always radial in direction, and the beginning of a wing springing from the upper right-hand limb of the sun.
By careful process painting, as already described, I have been able force up the value of the prominence reds, which appear in Figures 3 and 4 at about 67. I also concluded to reduce the value of the clear sky from 30 to
25, thus obtaining a range of 42 points instead of 30, an increase in the ratio of 7 to 5. In this new scale the other values take their proportional places. Thus a value of 35 (30+ 5) in Figure 1 becomes 32 (25+7) in Figure 3.
In Figure 3 the corona lines, derived from the drawing and many photographs, may be regarded as a sort of composite, suggesting contours of luminosity very much as contours of elevation appear on a map.
Three paintings were made, the first immediately after the eclipse, the second on the succeeding day, and the third after all data had been secured. This final painting is the one reproduced in conjunction with this article.
Returning with Professor Mitchell, we stopped at Williams Bay, Wisconsin, and I had the great pleasure and advantage of discussing the problems of the final picture with Professor E. E. Barnard and Dr. E. B. Frost, of the Yerkes Observatory. They also showed me excellent photographs taken at one of the Yerkes stations and spectroscopic photographs of the prominences taken at the Yerkes Observatory (at the time of totality at the Green River Station), apparently identical as to drawing with those taken at the Baker Station. I wish to acknowledge my indebtedness to these eminent astronomers.
The Eagle Prommence
June 8th 1913 F.R.B
WILD FLOWERS "FROM GREENLAND'S ICY MOUNTAIN"
Between lonely rocks and wild crags grow the flower gardens of the Arctic-poppies with nodding buds and ornamental leaves, the small white clustered Draba flowers, and green heads of Arctic timothy. There are about 120 species of flowering plants-and probably "new" species waiting to be discovered-in the ice-free land where the Smith Sound Eskimos live, along the northwestern coast of Greenland between Humboldt Glacier on the north and Melville Bay on the south-a strip made narrow by the ice cap above and the iceberg-studded sound below. Long months pass when the botanist has few specimens to work with, however. Not until the ice breaks out and midsummer is at hand are many flowers in bloom. There is no spring in the Arctic like ours, or rather, there is only our spring, and no summer. All the plants awake together and hasten to their fruitage as if to make the most of the few weeks of comparative warmth. With equal suddenness at the end of summer, the vegetation is caught in full activity, and stiffened as it stands, with seeds half formed, or perhaps with buds, or open flowers
The Plant Life of Northwest Greenland
By W. ELMER EKBLAW
Research Associate, American Museum of Natural History; Research Fellow in Geology, University of Illinois; and Geologist and Botanist on the Crocker Land Expedition, 1913-1917
EW people of our pleasant southland even dream that under the shadow of the North Pole, almost a thousand miles within the Arc
tic circle, more
than one hun
dred species of flowering plants flourish
and maintain themselves against the frigid conditions of their far northern home. Yet, in the country of the Smith Sound Eskimo, a narrow belt of ice-free land between the gleaming ice cap and the icebergstudded sound, from Cape York to Humboldt Glacier, botanists have already recorded 120 species, and the list is no doubt yet incomplete. No tall trees or branching shrubs, no trailing vines or waist-high grasses give character to the landscape, but the rocky slopes and ledges are dotted in summer with brilliant blossoms or carpeted with low, soft growths of grass or sedge.
When the explorer from the south land approaches the rock-bound, glacierribboned coasts of Greenland, his first impression is one of bleakness and barrenness. The frowning cliffs, stern and
unchangeable, the gleaming glaciers, cold and immobile, suggest no possible refuge for flowers, no likely niche for ferns or grasses. But in summer when
he enters some little bay, or goes up one of the deep fiords and sets his foot upon the land, he finds that Greenland is not so cold, nor so bleak, nor SO barren as he imagined. Every little crevice in the rocks is foothold for some fern or glowing flower, every little pocket of soil refuge for a bit of verdant turf, and every little slope or ledge shelter for willow, heather, or smiling poppy.
How can they grow and blossom and fruit in the short summer, when the snow begins to disappear only in mid-June, and killing frosts come in mid-August; when the warmest noonday has never a temperature higher than sixty degrees and storms often blanket the whole land with snow, even in mid-July? It is because the plants that hold their homes under these rigorous conditions are adapted to make the most of the twenty-four hour sunlight that shines