Trail .si tori ness 

 Tree 



SCIENTIFIC SIDE-LIGHTS 



702 



3473. TRANSITORINESS OF HUMAN 

 MEMORIALS We can foresee no limit to 

 the perpetuation of some of the memorials 

 of man, which are continually entombed in 

 the bowels of the earth or in the bed of the 

 ocean. . . . 



Yet it is no less true, as a late distin- 

 guished philosopher [Davy] has declared, 

 " that none of the works of a mortal being 

 can be eternal." They are in the first place 

 wrested from the hands of man, and lost 

 as far as regards their subserviency to his 

 use, by the instrumentality of those very 

 causes which place them in situations where 

 they are enabled to endure for indefinite 

 periods. And even when they have been 

 included in rocky strata, when they have 

 been made to enter, as it were, into the solid 

 framework of the globe itself, they must 

 nevertheless eventually perish; for every 

 year some portion of the earth's crust is 

 shattered by earthquakes, or melted by vol- 

 canic fire, or ground to dust by the moving 

 waters on the surface. " The river of Lethe," 

 as Bacon eloquently remarks, " runneth as 

 well above ground as below." LYELL Prin- 

 ciples of Geology, bk. iii, ch. 48, p. 764. (A., 

 1854.) 



3474. TRANSITORINESS OF LAND- 

 FORMATIONS Islands Built Up and Des- 

 troyed in the Ganges. Major R. H. Cole- 

 brooke, in his account of the course of the 

 Ganges, relates examples of the rapid filling 

 up of some of its branches, and the exca- 

 vation of new channels, where the number of 

 square miles of soil removed in a short time 

 (the column of earth being 114 feet high) 

 was truly astonishing. Forty square miles, 

 or 25,600 acres, are mentioned as having 

 been carried away, in one place, in the 

 course of a few years. The immense trans- 

 portation of earthy matter by the Ganges 

 and Brahmaputra is proved by the great 

 magnitude of the islands formed in their 

 channels during a period far short of that 

 of a man's life. Some of these, many 

 miles in extent, have originated in large 

 sand-banks thrown up round the points at 

 the angular turning of the rivers, and after- 

 wards insulated by breaches of the streams. 

 Others, formed in the main channel, are 

 caused by some obstruction at the bottom. 

 A large tree or a sunken boat is sometimes 

 sufficient to check the current, and cause 

 a deposit of sand, which accumulates till 

 it usurps a considerable portion of the chan- 

 nel. The river then undermines its banks 

 on each side to supply the deficiency in its 

 bed, and the island is afterwards raised 

 by fresh deposits during every flood. In 

 the great gulf below Luckipour, formed by 

 the united waters of the Ganges and Megna, 

 some of the islands, savs Rennell, rival in 

 size and fertility the Isle of Wight. While 

 the river is forming new islands in one part, 

 it is sweeping away old ones in others. 

 Those newly formed are soon overrun with 

 reeds, long grass, the Tamarix Indica, and 



other shrubs, forming impenetrable thickets, 

 where the tiger, the rhinoceros, the buffalo, 

 deer, and other wild animals, take shelter. 

 It is easy, therefore, to perceive that both 

 animal and vegetable remains may occa- 

 sionally be precipitated into the flood and 

 become embedded in the sediment which sub- 

 sides in the delta. LYELL Principles of Ge- 

 ology, bk. ii, ch. 18, p. 277. (A., 1854.) 



3475. TRANSITORINESS OF OUR 



UNIVERSE Some Greater All-embracing Re- 

 ality. These impressions are strengthened 

 rather than weakened when we come back 

 from the outer universe to our own little 

 solar system; for every process which we 

 know tends to the dissipation, or rather the 

 degradation, of heat, and seems to point, 

 in our present knowledge, to the final decay 

 and extinction of the light of the world. 

 In the words of one of the most eminent 

 living students of our subject, " The candle 

 of the sun is burning down, and, as far as 

 we can see, must at last reach the socket. 

 Then will begin a total eclipse which will 

 have no end. 



' Dies irse, dies ilia, 

 Solvet sseclum in favilla.' " 



Yet tho it may well be that the fact itself 

 here is true, it is possible that we draw 

 the moral to it unawares, from an unacknowl- 

 edged satisfaction in the idea of the vastness 

 of the funeral pyre provided for such beings 

 as ourselves, and that it is pride, after all, 

 which suggests the thought that when the 

 sun of the human race sets, the universe 

 will be left tenantless, as a body from which 

 the soul has fled. Can we not bring our- 

 selves to admit that there may be something 

 higher than man and more enduring than 

 frail humanity, in some sphere in which 

 our universe, conditioned as it is in space 

 and time, is itself embraced, and so distrust 

 the conclusions of man's reason where they 

 seem to flatter his pride? LANGLEY The 

 ~New Astronomy, ch. 8, p. 249. (H. M. & Co., 

 1896.) 



3476. TRANSMISSION OF RADIANT 

 HEAT Adventure on Railroad Power of Un- 

 seen Forces. I once had an opportunity to 

 observe the wonderful rapidity with which 

 light and radiant heat are transmitted 

 through glass, which is transparent to both. 

 I was at Vancouver, at the terminus of the 

 Canadian Pacific Railway, on Burrard In- 

 let. We started for Winnipeg about noon, 

 and six miles out the train was stopped by 

 a burning woodpile of large dimensions with- 

 in a few feet of the track. After two hours 

 of waiting the wood had been reduced to a 

 huge pile of glowing coals. The conductor 

 concluded to run past at a high ra-te of 

 speed; so backing up about one-half mile 

 they put on a full head of steam and ran 

 past the fire at a tremendous speed. I was 

 in a stateroom, and the passageway around 

 it was between me and the fire, so that the 

 heat and light had to pass through two win- 



