ear- 



SCIENTIFIC SIDE-LIGHTS 



148 



ceived by Janson in 1600 to show fluctua- 

 tions of light, and Montanari found, in 1669, 

 that Algol in Perseus shared the same pe- 

 culiarity to a marked degree. Altogether 

 the class embraced, in 1782, half a dozen 

 members. When it is added that a few star 

 couples had been noted in singularly, but it 

 was supposed accidentally, close juxtaposi- 

 tion, and that the failure of repeated at- 

 tempts to find an annual parallax pointed to 

 distances for the stars at least 400,000 times 

 that of the earth from the sun, the picture 

 of sidereal science, when the last quarter of 

 the eighteenth century began, is practically 

 complete. It included three items of infor- 

 mation: that the stars have motions, real 

 or apparent; that they are immeasurably 

 remote; and that a few shine with a period- 

 ically variable light. Nor were the facts 

 thus scantily collected ordered into any 

 promise of further development. They lay 

 at once isolated and confused before the in- 

 quirer. They needed to be both multiplied 

 and marshaled, and it seemed as if cen- 

 turies of patient toil must elapse before any 

 reliable conclusions could be derived from 

 them. The sidereal world was thus the 

 recognized domain of far-reaching specula- 

 tions, which remained wholly uncramped by 

 systematic research until Herschel entered 

 upon his career as an observer of the 

 heavens. CLERKE History of Astronomy, ch. 

 1, p. 12. (Bl., 1893.) 



727. DARKNESS, COLD, AND PRES- 

 SURE IN DEEP SEA "In the Lowest Pit, 

 in Darkness, in the Deeps " (Ps. Ixxxviii, 6). 

 The peculiar physical conditions of the 

 deep seas may be briefly stated to be these: 

 It is absolutely dark so far as actual sun- 

 light is concerned, the temperature is only 

 a few degrees above freezing-point, the pres- 

 sure is enormous, there is little or no move- 

 ment of the water, the bottom is composed 

 of a uniform fine soft mud, and there is no 

 plant-life. All of these physical conditions 

 we can appreciate except the enormous pres- 

 sure. Absolute darkness we know, the tem- 

 perature of the deep seas is not an extraor- 

 dinary one, the absence of movement in the 

 water and the fine soft mud are conditions 

 that we can readily appreciate; but the 

 pressure is far greater than anything we 

 can realize. HICKSON Fauna of the Deep 

 Sea, ch. 2, p. 18. (A., 1894.) 



728. DARKNESS IN THE DAYTIME 



Far-reaching Effect of Earthquake. In 

 April, 1815, one of the most frightful erup- 

 tions recorded in history occurred in the 

 province of Tomboro, in the island of Sum- 

 bawa, about 200 miles from the eastern ex- 

 tremity of Java. . . . The sound of the 

 explosions was heard in Sumatra, at the dis- 

 tance of 970 geographical miles in a direct 

 line; and at Ternate, in an opposite direc- 

 tion, at the distance of 720 miles. Out of a 

 population of 12,000, in the province of 

 Tomboro. only twenty-six individuals sur- 

 vived. Violent whirlwinds carried up men, 



horses, cattle, and whatever else came 

 within their influence into the air; tore up 

 the largest trees by the roots, and covered 

 the whole sea with floating timber. Great 

 tracts of land were covered by lava, several 

 streams of which, issuing from the crater 

 of the Tomboro mountain, reached the sea. 

 So heavy was the fall of ashes that they 

 broke into the Resident's house at Bima, 

 forty miles east of the volcano, and ren- 

 dered it, as well as many other dwellings in 

 the town, uninhabitable. On the side of 

 Java the ashes were carried to the distance 

 of 300 miles, and 217 towards Celebes, in 

 sufficient quantity to darken the air. The 

 floating cinders to the westward of Sumatra 

 formed, on the 12th of April, a mass two feet 

 thick, and several miles in extent, through 

 which ships with difficulty forced their 

 way. 



The darkness occasioned in the daytime 

 by the ashes in Java was so profound that 

 nothing equal to it was ever witnessed in 

 the darkest night. Altho this volcanic dust 

 when it fell was an impalpable powder, it 

 was of considerable weight when compressed, 

 a pint of it weighing twelve ounces and 

 three-quarters. " Some of the finest parti- 

 cles," says Mr. Crawiurd, "were transported 

 to the islands of Amboyna and Banda, which 

 last is about 800 miles east from the site of 

 the volcano, altho the southeast monsoon 

 was then at its height." They must have 

 been projected, therefore, into the upper re- 

 gions of the atmosphere, where a counter- 

 current prevailed. LYELL Principles of Ge- 

 ology, bk. ii, ch. 27, p. 465. (A., 1854.) 



729. DARKNESS REVEALS The 



Sun's Bright Corona Seen Only During 

 Eclipse Unnatural Light Attending Eclipse. 

 I have witnessed three total eclipses, but I 

 do not find that repetition dulls the interest. 

 The first was that of 1869, which passed 

 across the United States and was nearly 

 central over Louisville. My station was on 

 the southern border of the eclipse track, not 

 very far from the Mammoth Cave in Ken- 

 tucky, and I well remember that early ex- 

 perience. The special observations of pre- 

 cision in which I was engaged would not 

 interest the reader ; but while trying to give 

 my undivided attention to these, a mental 

 photograph of the whole spectacle seemed to 

 be taking without my volition. First, the 

 black body of the moon advanced slowly on 

 the sun, as we have all seen it do in partial 

 eclipses, without anything noticeable ap- 

 pearing; nor till the sun was very nearly 

 covered did the light of day about us seem 

 much diminished. But when the sun's face 

 was reduced to a very narrow crescent, the 

 change was sudden and startling, for the 

 light which fell on us not only dwindled rap- 

 idly, but became of a kind unknown before, 

 so that a pallid appearance overspread the 

 face of the earth with an ugly livid hue; 

 and as this strange wanness increased, a 

 cold seemed to come with it. The impres- 



