wee 



"oresta 



SCIENTIFIC SIDE-LIGHTS 



266 



was labor of an unexacting and most fruit- 

 ful kind. So, too, when heat-engines of con- 

 stantly improved types came into the mines, 

 the shops, and factories of the world, and 

 were last of all adapted to transportation, 

 the work that a skilful man could direct be- 

 came immensely greater and bolder than the 

 task he could perform by dint of exerting 

 his own muscles. In this passing to more 

 and more of initiative consists an important 

 phase of civilization. ILES Flame, Electric- 

 ity, and the Camera, ch. 5, p. 63. (D. & 

 McC., 1900.) 



1298. FORCES, ELEMENTAL, MADE 

 TO WORK FOR MAN Transformation of 

 Industry From Shadoof to Water-wheel. 

 In the period of ancient civilization there 

 appear the beginnings of that immense 

 change which is remodeling modern life, 

 by inventions which set the forces of Nature 

 to do man's heavy work for him. This 

 great change seems to have been especially 

 brought on by contrivances to save the 

 heavy toil of watering the fields. A simple 

 hand-labor contrivance of this kind is the 

 shadoof of the Nile Valley, where a long pole 

 with a counterpoise at one end is supported 

 on posts, and carries a bucket hanging to 

 the longer end to dip up water from below. 



. For irrigation, it was mechan- 

 ically an improvement on this to set a gang 

 of slaves to turn a great wheel with buckets 

 or earth ern jars at its circumference, which 

 rose full from the water below, and as they 

 turned over emptied themselves into a 

 trough at a higher level. But when such a 

 wheel was built to dip in a running stream, 

 then the current itself would turn the wheel, 

 and thus would come into existence the 

 noria, or irrigating water-wheel, often men- 

 tioned in ancient literature, and to be seen 

 still at work both in the East and in Eu- 

 rope. - By these or some similar steps of in- 

 vention the water-wheel was made a source 

 of power for doing other work, such as 

 grinding corn, instead of the women at the 

 quern or the slaves at the treadmill, or the 

 mill-horse in his everlasting round. As 

 the Greek epigram says, " Cease your work, 

 ye maids who labored at the mills, sleep and 

 let the birds sing to the returning dawn, for 

 Demeter has bidden the water-nymphs to do 

 your task; obedient to her call, they throw 

 themselves on the wheel and turn the axle 

 and the heavy mill." TYLOB Anthropology, 

 ch. 8, p. 203. (A., 1899.) 



1299. FORCES, MATERIAL AND MEN- 

 TAL Every Force Perhaps a Manifestation of 

 Will. Undoubtedly the first thought which 

 suggests itself to the mind is, that a ma- 

 terial force and a moral or intellectual force 

 are essentially different in kind not sub- 

 ject to conditions the same, or even similar. 

 But are we sure of this? Are we sure that 

 the forces which we call material are not, 

 after all, but manifestations of mental en- 

 ergy and will? We have already seen that 

 such evidence as we have is all tending the 



other way. The conclusions forced upon us 

 have been these: First, that the more we 

 know of Nature the more certain it appears 

 that a multiplicity of separate forces does 

 not exist, but that all her forces pass into 

 each other, and are but modifications of 

 some one force which is the source and cen- 

 ter of the rest; secondly, that all of them 

 as-e governed in their mutual relations by 

 principles of arrangement which are purely 

 mental; thirdly, that of the ultimate seat 

 of force in any form we know nothing di- 

 rectly; and fourthly, that the nearest con- 

 ception we can ever have of force is derived 

 from our own consciousness of vital power. 

 ARGYLL Reign of Law, ch. 6, p. 164. 

 (Burt.) 



1300. FORCES OF NATURE NOT 

 BLIND The. Blindness Is in Man Snow- 

 crystals. When snow is produced in calm 

 air, the icy particles build themselves into 

 beautiful stellar shapes, each star possessing 

 six rays. There is no deviation from this 

 type, tho in other respects the appearances of 

 the snow-stars are infinitely various. . . . 

 It is worth pausing to think what wonderful 

 work is going on in the atmosphere during 

 the formation and descent of every snow- 

 shower: what building power is brought 

 into play! and how imperfect seem the 

 productions of human minds and hands 

 when compared with those formed by the 

 blind forces of Nature! 



But who ventures to call the forces of 

 Nature blind? In reality, when we speak 

 thus, we are describing our own condition. 

 The blindness is ours; and what we really 

 ought to say, and to confess, is that our 

 powers are absolutely unable to compre- 

 hend the origin or the end of the operations 

 of Nature. TYNDALL Forms of Water, 89, 

 p. 31. (A., 1899.) 



1301. FORCES, TITANIC, OF NATURE 



Kocks Ground to Impalpable Powder. 

 During their upward discharge and down- 

 ward fall, the cindery fragments are by at- 

 trition continually reduced to smaller di- 

 mensions. The noise made by these frag- 

 ments, as they strike against one another 

 in the air during their rise and fall, is one 

 of the most noteworthy accompaniments of 

 volcanic eruptions. It has been noticed 

 that in many cases there is a constant dim- 

 inution in the size of the fragments ejected 

 during a volcanic outburst, this being doubt- 

 less due to the friction of the masses as 

 they are ejected and reejected from the 

 vent. Thus it is related by Mr. Poulett 

 Scrope, who watched the Vesuvian eruption 

 of 1822, which lasted for nearly a month, 

 that during the earlier stages of the out- 

 burst fragments of enormous size were 

 thrown out of the crater, but by constant 

 reejection these were gradually reduced in 

 size, till at last only the most impalpable 

 dust issued from the vent. This dust filled 

 the atmosphere, producing in the city of 

 Naples " a darkness that might be felt," 



