709 



SCIENTIFIC SIDE-LIGHTS 



Ellltll 

 niformity 



in the psychology of belief than the univer- 

 sality with which even the most wonderful 

 I might say the most romantic results 

 of spectrum analysis have been accepted as 

 sober truth, not merely by the whole scien- 

 tific world, but by the general public. And 

 this universality is, I think, to be attributed 

 to these two conditions: first, that the ab- 

 solute concurrence of scientific men on this 

 subject gives to their statements the value 

 (if I may so express myself) of bank-notes, 

 which any one may convert into the stand- 

 ard gold of personal knowledge merely by 

 inquiring into the matter for himself; and 

 secondly, that these results are additions 

 to our previous knowledge, and do not run 

 counter to any established beliefs. CARPEN- 

 TER Nature and Man, lect. 7, p. 236. (A., 

 1889.) 



35O9. UNCERTAINTY INEVITABLE 



Atmosphere of Venus Makes Exact Obser- 

 vation of Transit Impossible. [At the tran- 

 sit of Venus, 1874] an appearance super- 

 vened which took most observers by surprise. 

 This was the illumination due to the atmos- 

 phere of Venus. Astronomers, it is true, 

 were not ignorant that the planet had, on 

 previous occasions, been seen girdled with a 

 lucid ring; but its power to mar observa- 

 tions by the distorting effect of refraction 

 had scarcely been reckoned with. It proved, 

 however, to be very great. Such was the 

 difficulty of determining the critical instant 

 of internal contact, that (in Colonel Tup- 

 man's words) " observers side by side, with 

 adequate optical means, differed as much 

 as twenty or thirty seconds in the times 

 they recorded for phenomena which they 

 have described in almost identical language." 

 CLERKE History of Astronomy, pt. ii, ch. 

 6, p. 291. (Bl., 1893.) 



35 1C. UNIFICATION OF THE SCI- 

 ENCES Astronomy Needs and Aids All Other 

 Science The Universe an Intellectually 

 Consistent Whole. The unification of the 

 physical sciences is perhaps the greatest in- 

 tellectual feat of recent times. The process 

 has included astronomy; so that, like Bacon, 

 she may now be said to have "taken all 

 knowledge" (of that kind) "for her prov- 

 ince." In return, she proffers potent aid for 

 its increase. Every comet that approaches 

 the sun is the scene of experiments in the 

 electrical illumination of rarefied matter, 

 performed on a huge scale for our benefit. 

 The sun, stars, and nebulae form so many 

 celestial laboratories, where the nature and 

 mutual relations of the chemical " ele- 

 ments " may be tried by more stringent tests 

 than sublunary conditions afford. The laws 

 of terrestrial magnetism can be completely 

 investigated only with the aid of a concur- 

 rent study of the face of the sun. The posi- 

 tions of the planets will perhaps one day 

 tell us something of impending droughts, 

 famines, and cyclones. CLERKE History of 

 Astronomy, int., p. 7. (Bl., 1893.) 



3511. UNIFORMITY OF NATURE- 



Ancient Sedimentary Deposits Like the Pres- 

 ent Geological Strata Forming Now. The 

 great bulk of the derivative rocks being of 

 sedimentary origin, it is obvious that they 

 must have been at the time of their forma- 

 tion spread out in approximately horizon- 

 tal layers upon the beds of ancient lakes 

 and seas. This we are justified in believing 

 by what we know of the accumulation of 

 similar sediments in our own day. The 

 wide flats of our river-valleys, the broad 

 plains that occupy the sites of silted-up 

 lakes, the extensive deltas of such rivers 

 as the Nile, the Po, the Amazon, the Mis- 

 sissippi, the narrow or wide belts of low- 

 lying land which within a recent period have 

 been gained from the sea, are all made up 

 of various kinds of sediment arranged in 

 gently inclined or approximately horizontal 

 layers. Now, over considerable areas of the 

 earth's surface the derivative rocks show 

 the same horizontal arrangement, a struc- 

 ture which is obviously original. GEIKIE 

 Earth Sculpture, ch. 1, p. 7. (G. P. P., 

 1898.) 



3512. Ancient Volcanic 



Action Like the Modern Fertility and Hap- 

 piness in the Intervals. If we look at the 

 vast masses of volcanic materials erupted 

 in Miocene times in our own island and 

 in Ireland, for example, we might be led 

 to imagine that we have the indications 

 of a veritable " reign of fire," and that the 

 evidence points to a condition of things 

 very different indeed from that which pre- 

 vails at the present day. But [we must re- 

 member] that these volcanic ejections are 

 not the result of one violent effort, but are 

 the product of numerous small outbreaks 

 which have been scattered over enormous 

 periods of time. 



When we examine with due care the lavas, 

 tuffs, and other volcanic ejections which 

 constitute such mountain masses as those 

 of the Hebrides, of the Auvergne, and of 

 Hungary, we find clear proofs that the an- 

 cient Miocene volcanoes of these districts 

 were clothed with luxuriant forests, through 

 which wild animals roamed in the greatest 

 abundance. The intervals between the ejec- 

 tions of successive lava-streams were often 

 so great that soils were formed on the moun- 

 tain slope, and streams cut deep ravines 

 and valleys in them. JUDD Volcanoes, ch. 9, 

 p. 278. (A., 1899.) 



3513. A Revelation of 



the Immutability of God. The chemist in 

 his laboratory, as he questions Nature, may 

 be almost said to put her to the torture 

 when, tried in his hottest furnace, or probed 

 by his searching analysis to her innermost 

 arcana, she by a spark or an explosion, or an 

 effervescence, or an evolving substance, 

 makes her distinct replies to his investiga- 

 tions. And ... in every quarter of the 

 globe her answer is the same so that, let 

 the experiment, tho a thousand times re- 



