sasr 



hood 



SCIENTIFIC SIDE-LIGHTS 



84 



of mankind." [Quoted from Wilhelm von 

 Humboldt.J HUMBOLDT Cosmos, vol. i, p. 

 358. (H., 1897.) 



41O. BUBBLE AND FROG Elementary 

 Law Has No Adaptation to Circumstance. 

 Blow bubbles through a tube into the bot- 

 tom of a pail of water, they will rise to the 

 surface and mingle with the air. Their ac- 

 tion may again be poetically interpreted as 

 due to a longing to recombine with the 

 mother-atmosphere above the surface. But 

 if you invert a jar full of water over the 

 pail, they will rise and remain lodged be- 

 neath its bottom, shut in from the outer air, 

 altho a slight deflection from their course 

 at the outset, or a redescent towards the 

 rim of the jar when they found their up- 

 ward course impeded, would easily have set 

 them free. Suppose a living frog in the po- 

 sition in which we placed our bubbles of air, 

 namely, at the bottom of a jar of water. 

 The want of breath will soon make him also 

 long to rejoin the mother-atmosphere, and 

 he will take the shortest path to his end by 

 swimming straight upwards. But if a jar 

 full of water be inverted over him, he will 

 not, like the bubbles, perpetually press his 

 nose against its unyielding roof, but will 

 restlessly explore the neighborhood until by 

 redescending again he has discovered a path 

 round its brim to the goal of his desires. 

 JAMES Psychology, vol. i, ch. 1, p. 7. (H. 

 H. & Co., 1899.) 



411. BUILDINGS, ANCIENT, UNDER- 

 MINED BY WORMS Subsidence and Crack- 

 ing of Walls, Cause of. Worms have 

 played a considerable part in the burial and 

 concealment of several Roman and other old 

 buildings in England; but no doubt the 

 washing down of soil from the neighboring 

 higher lands, and the deposition of dust, 

 have together aided largely in the work of 

 concealment. Dust would be apt to accumu- 

 late wherever old broken-down walls pro- 

 jected a little above the then existing sur- 

 face and thus afforded some shelter. The 

 floors of the old rooms, halls, and passages 

 have generally sunk, partly from the set- 

 tling of the ground, but chiefly from hav- 

 ing been undermined by worms; and the 

 sinking has commonly been greater in the 

 middle than near the walls. The walls 

 themselves, whenever their foundations do 

 not lie at a great depth, have been pene- 

 trated and undermined by worms, and have 

 consequently subsided. The unequal sub- 

 sidence thus caused probably explains the 

 great cracks which may be seen in many 

 ancient walls, as well as their inclination 

 from the perpendicular. DARWIN Forma- 

 tion of Vegetable Mould, ch. 4, p. 68. 

 (Hum., 1887.) 



412. BUTTRESSES, NATURAL- Sup- 

 porting Roots of the Brazilian Pashiuba 

 Tree Stands as if on Stilts Strange Result 

 of Struggle for Life. My guide put me 

 ashore in one place to show me the roots of 



the Pashiuba. These grow above ground, 

 radiating from the trunk many feet above 

 the surface, so that the tree looks as if sup- 

 ported on stilts; and a person can, in old 

 trees, stand upright among the roots with 

 the perpendicular stem wholly above his 

 head. It adds to the singularity of their 

 appearance that these roots, which have the 

 form of straight rods, are studded with 

 stout thorns, while the trunk of the tree is 

 quite smooth. The purpose of this curious 

 arrangement is, perhaps, similar to that of 

 the buttress-roots already described name- 

 ly, to recompense the tree by root-growth 

 above the soil for its inability, in conse- 

 quence of the competition of neighboring 

 roots, to extend it underground. The great 

 amount of moisture and nutriment con- 

 tained in the atmosphere may also favor 

 .these growths. BATES Naturalist on the 

 River Amazon, ch. 5, p. 661. (Hum., 1880.) 



413. CALCULATION, ANCIENT, BY 

 PEBBLES Language Preserves the Story of 

 Early Arithmetic. In Africa, negro traders 

 may be seen at market reckoning with peb- 

 bles, and when they come to five, putting 

 them aside in a little heap. In the South 

 Sea Islands it has been noticed that people 

 reckoning, when they came to ten, would 

 not put aside a heap of ten things, but only 

 a single bit of coconut stalk to stand for 

 ten, and then a bigger piece when they 

 wanted to represent ten tens or a hundred. 

 Now to us it is plain that this use of differ- 

 ent kinds of markers is unnecessary, but all 

 that the reckoner with little stones or beans 

 has to do is to keep separate his unit-heap, 

 his ten-heap, his hundred-heap, etc. This 

 use of such things as pebbles for " count- 

 ers," which still survives in England among 

 the ignorant, was so common in the ancient 

 world that the Greek word for reckoning 

 was psephizein, from psephos, a pebble, and 

 the corresponding Latin word was calculare, 

 from calculus, a pebble, so that our word 

 calculate is a relic of very early arithmetic. 

 TYLOR Anthropology, ch. 13, p. 313. (A., 

 1899.) 



414. CALCULATION VERIFIED-A 



Fine Test Utilizing the Moon Star-colors 

 Proved Real Varied Glory in Distant 

 Space. It was long thought that at least 

 the more strongly marked colors, in the case 

 of small companion stars, were due merely 

 to contrast. But the supposition that the 

 colors seen in double stars are due to con- 

 trast has been in several instances com- 

 pletely disposed of, by so arranging matters 

 that one star only of a pair is seen at a 

 time. This can readily be arranged where 

 the stars are not very close, and in a great 

 number of cases it has been found that the 

 small star, seen alone, was really blue or 

 green or purple, as the case might be. The 

 experiment was in one case tried in the case 

 of a very close pair, in a very interesting 

 way. The star in question is the ruddy 





