189 



SCIENTIFIC SIDE-LIGHTS 



ency; but it is covered with another ele- 

 ment, of a strange constitution, which ap- 

 pears to have neither body, nor stability, 

 nor continuance. It has neither color nor 

 density. It takes all forms, moves in all di- 

 rections, obeys all shocks, submits to all im- 

 pulses, is extended, contracted, condensed, 

 appears and disappears, without our being 

 able to imagine such strange metamorpho- 

 ses. This is the world of instability, the 

 planet of revolutions. It experiences in turn 

 all imaginable disasters. It seems to be 

 matter in fermentation, which tends to dis- 

 solve. We only see storms, cyclones, whirl- 

 winds, and acts of violence of all sorts. 

 They assert that there are inhabitants on 

 this planet; but on what point can they 

 live ? Is it on the solid element of the body ? 

 They would be crushed, suffocated, asphyxi- 

 ated, drowned by that element which weighs 

 on them from all sides. Is it through the 

 openings in this mobile curtain that they 

 can enjoy, as we do, the pure ether of the 

 heavens ? But how can we suppose that 

 they might not at any moment be torn from 

 the soil by the violence of the disorders 

 which torment the surface? Do they wish 

 to place them on the light and mobile 

 stratum which hides from us so often the 

 aspect of the terrestrial nucleus? How can 

 they be maintained upright on this element 

 without solidity? . . . There is no ne- 

 cessity for long consideration to prove con- 

 clusively that this planet is very vast, but 

 that it is no place for animated beings. 

 The whole earth is not worth the soul of a 

 single Selenite. If, however, they will insist 

 that it may have inhabitants, we will con- 

 sent with pleasure, provided that they com- 

 pare them with fantastic beings floating at 

 the pleasure of all the forces which contend 

 with each other on this aeriform planet. 

 There can only exist there rather coarse 

 animals. Such are, in our opinion, the only 

 inhabitants which can people the earth." 



The scientists of the moon have, as we 

 see, the ability to prove, in the most cate- 

 gorical manner, to the ignorant who sur- 

 round them, that the earth, not being habit- 

 able, should not be inhabited, and that it is 

 made solely to serve as a clock to the moon 

 and to shine during the night. FLAMMA- 

 RION Popular Astronomy, bk. ii, ch. 6, p. 

 159. (A.) 



929. EARTH, CONVULSIONS OF 



Ancient and Modern Catastrophes Com- 

 pared. We know that subterranean move- 

 ments and volcanic eruptions are often at- 

 tended not only by incursions of the sea, but 

 also by violent rains, and the complete de- 

 rangement of the river-drainage of the 

 inland country, and by the damming up of 

 the outlets of lakes by landslips, or obstruc- 

 tions in the courses of subterranean rivers, 

 such as abound in Thessaly and the Morea. 

 We need not therefore be surprised at the 

 variety of causes assigned for the tradi- 

 tional floods of Greece, by Herodotus, Aris- 

 totle, Diodorus, Strabo, and others. As to 



the area embraced, had all the Grecian del- 

 uges occurred simultaneously, instead of 

 being spread over many centuries, and had 

 they, instead of being extremely local, 

 reached at once from the Euxine to the 

 southwestern limit of the Peloponnesus, and 

 from Macedonia to Rhodes, the devastation 

 would still have been more limited than that 

 which visited Chile in 1835, when a volcanic 

 eruption broke out in- the Andes, opposite 

 Chiloe, and another at Juan Fernandez, dis- 

 tant 720 geographical miles, at the same 

 time that several lofty cones in the Cor- 

 dillera, 400 miles to the eastward of that 

 island, threw out vapor and ignited matter. 

 Throughout a great part of the space thus 

 recently shaken in South America, cities 

 were laid in ruins, or the land was per- 

 manently upheaved, or mountainous waves 

 rolled inland from the Pacific. LYELL Prin- 

 ciples of Geology, bk. ii, ch. 22, p. 357. (A., 

 1854.) 



930. EARTH, COOLING AND CON- 

 TRACTION OF Earthquakes and Volcanoes 

 Mightier in Early Times. The general re- 

 sult which we should arrive at would be that 

 in past ages the loss of heat was more rapid 

 than it is at present. Now the contraction 

 of a body as it cools is for low tempera- 

 tures proportional to its loss of heat, and 

 this law is also probably true for contrac- 

 tion as it takes place from high tempera- 

 tures. Contraction of the earth's nucleus be- 

 ing more rapid than it is at present, it is 

 probable that phenomena like elevations and 

 depressions would be more rapid than they 

 are at present, and generally all changes 

 due to Plutonic action, as has already been 

 pointed out by Lord Kelvin (Sir William 

 Thomson), must have been more frequent 

 and intense than they are at the present 

 day. We have, therefore, every reason to 

 imagine that earthquakes which belong to 

 the category of phenomena here referred to 

 were also numerous and occurred on a 

 grander scale during the earlier stages of 

 the world's history than they do at present, 

 and seismic and volcanic energy, when con- 

 sidered in reference to long periods of time, 

 is probably a decreasing energy. MILNE 

 Earthquakes, ch. 13, p. 236. (A., 1899.) 



931. EARTH, DESTRUCTION AND 

 RENOVATION OF ITS SURFACE Theory 

 of Aristotle. When we consider the ac- 

 quaintance displayed by Aristotle, in his 

 various works, with the destroying and ren- 

 ovating powers of Nature, the introductory 

 and concluding passages of the twelfth chap- 

 ter of his " Meteorics " are certainly very 

 remarkable. In the first sentence he says, 

 " The distribution of land and sea in par- 

 ticular regions does not endure throughout 

 all time, but it becomes sea in those parts 

 where it was land, and again it becomes land 

 where it was sea; and there is reason for 

 thinking that these changes take place ac- 

 cording to a certain system, and within a 

 certain period." The concluding observation 



