669 



SCIENTIFIC SIDE-LIGHTS 



Bun 

 Sunshine 



bratory motion of the atoms. We can now 

 convert at will all motion into heat, and 

 all heat into motion. The motion of con- 

 densation has sufficed, and more than 

 sufficed, to produce the present temperature 

 of the sun and the original temperature of 

 all the planets. If that brilliant star con- 

 tinues to condense, as is probable, a conden- 

 sation which would shorten its diameter 

 by v fo v of its present length would produce 

 a quantity of heat sufficient to cover the 

 loss by emission during two thousand years. 

 At the present rate of emission the solar 

 heat produced by the earlier condensation 

 of its mass would still last for 20 millions 

 of years. FLAMMARION Popular Astronomy, 

 bk. i, ch. 7, p. 75. (A.) 



3308. SUN'S SURFACE PHOTO- 

 GRAPHED Under the Camera Photograph 

 Secures Details Invisible to the Eye Open- 

 ings in an Atmosphere of Vaporized Metal 

 Reality Surpassing Wildest Dream. The 

 photograph has transported us already so 

 near the sun's surface that we have seen 

 details there invisible to the naked eye. 



What we have called " spots " 

 are indeed regions whose actual vastness 

 surpasses the vague immensity of a dream, 

 and it will not cause surprise that in them 

 is a temperature which also surpasses great- 

 ly that of the hottest furnace. . . . The 

 whole surface is composed largely of metals 

 turned into vapor in this heat, and . . . 

 if we could indeed drop our great globe 

 itself upon the sun it would be dissipated 

 as a snowflake. LANGLEY New Astronomy, 

 ch. 1, p. 19. (H. M. & Co., 1896.) 



3309. SUNNY FRANCE BURIED 

 UNDER ICE The Glacial Epoch. At the 

 time of the maximum extension of the 

 ice-sheet almost the whole of the Swiss 

 lowland was buried, and the ice welled 

 up against the flanks of the Jura to a height 

 of 3,000 feet above the Lake of Neuchatel, 

 whence it extended northward to the neigh- 

 borhood of Soleure. Along the present 

 course of the Rhone it sent out a huge lobe 

 far beyond the frontier of Switzerland, for 

 erratics [scattered boulders] and other gla- 

 cial deposits have been traced to within a 

 few miles of Lyons. It is estimated that 

 altogether the ancient glacier of the Rhone 

 was not less than 270 miles in length. BON- 

 NEY Ice-work, Present and Past, pt. i, ch. 1, 

 p. 35. (A., 1896.) 



33 1C. SUNSET MADE BEAUTIFUL 

 BY DUST Owing to the constant presence 

 of air currents, arranging both the dust and 

 vapor [in the atmosphere] in strata of vary- 

 ing extent and density, and of high or low 

 clouds, which both absorb and reflect the 

 light in varying degrees, we see produced 

 all those wondrous combinations of tints 

 and those gorgeous ever-changing colors 

 which are a constant source of admiration 

 and delight to all who have the advantage 

 of an uninterrupted view to the west, and 



who are accustomed to watch for these 

 not unfrequent exhibitions of Nature's kalei- 

 doscopic color-painting. With every change 

 in the altitude of the sun the display 

 changes its character, and most of all when 

 it has sunk below the horizon, and, owing 

 to the more favorable angles, a larger quan- 

 tity of the colored light is reflected toward 

 us. Especially when there- is a certain 

 amount of cloud is this the case. These, 

 so long as the sun was above the horizon, 

 intercepted much of the light and color; 

 but when the great luminary has passed 

 away from our direct vision his light 

 shines more directly on the under sides 

 of all the clouds and air strata of different 

 densities; a new and more brilliant light 

 flushes the western sky, and a display of 

 gorgeous, ever-changing tints occurs which 

 are at once the delight of the beholder and 

 the despair of the artist. And all this un- 

 surpassable glory we owe to dust! WAL- 

 LACE The Wonderful Century, ch. 9, p. 75. 

 (D. M. & Co., 1899.) 



3311. SUNSET MERGING INTO SUN- 

 RISE Effect of Atmospheric Refraction The 

 Midnight Sun at Tornea. It is not neces- 

 sary to go to the polar circle in order to 

 see the sun not setting and grazing the 

 horizon at midnight. At the sixty-sixth 

 degree of latitude in Sweden and Fin- 

 land we can enjoy this spectacle, so strange 

 to us the midnight sun. It has even 

 become the fashion in recent years to make 

 a voyage to Tornea, a little town on the 

 frontiers of Russia and Sweden, on the 

 Gulf of Bothnia, and to be present on June 

 21 on Mount Avasaxa, only 227 meters high, 

 when the sun does not set at the summer 

 solstice. FLAMMARION Popular Astronomy, 

 bk. i, ch. 2, p. 30. (A.) 



3312. SUNSHINE, DECREASE OF, 

 IN ENGLAND The Vine Once Freely Grown 

 The Dust from Manufactories Changing 

 a Nation's Climate. Now, there is much evi- 

 dence to show that there has been a consid- 

 erable increase in the amount of cloud, and 

 consequent decrease in the amount of sun- 

 shine, in all parts of our country. It is an 

 undoubted fact that in the Middle Ages Eng- 

 land was a wine-producing country, and this 

 implies more sunshine than we have now. 

 . . . Some years back one of our garden- 

 ing periodicals obtained from gardeners of 

 forty or fifty years' experience a body of 

 facts clearly indicating a comparatively 

 recent change of climate. It was stated 

 that in many parts of the country, es- 

 pecially in the north, fruits were formerly 

 grown successfully and of good quality in 

 gardens where they cannot be grown now. 

 . . . But an increase of cloud, and conse- 

 quent diminution of sunshine, would pro- 

 duce just such a result; and this increase 

 is almost certain to have occurred, owing 

 to the enormously increased amount of dust 

 thrown into the atmosphere as our country 

 has become more densely populated, and es- 



