Invention 

 Invisible 



SCIENTIFIC SIDE-LIGHTS 



360 



its intensity should be very feeble and quan- 

 tity small cannot be considered wonderful 

 when it is remembered that, like thermo- 

 electricity, it is evolved entirely within the 

 substance of metals retaining all their con- 

 ducting power." The steam-engine has ex- 

 alted this apparently feeble effect discov- 

 ered by Faraday into a power which is only 

 limited by that of the steam-engine or the 

 water-power which we employ. TROWBRIDGE 

 What is Electricity? ch. 1, p. 9. (A., 1899.) 



1756. INVENTION INDIGENOUS IN 



MAN Invention is indigenous in the na- 

 ture of man. The first being on this earth 

 worthy of that name was an inventor. The 

 only moment in the life of an individual or 

 a people in which the distinction of true hu- 

 manity may be worthily bestowed on them 

 is that in which something new is added to 

 the stock of knowledge or experience. When 

 men or nations originate, they live and 

 grow; when they cease to do that, they de- 

 cay and die. This has been true from the 

 beginning. MASON Origins of Invention, 

 ch. 12, p. 410. (S., 1899.) 



1757. INVENTION OF THE SAND- 

 BLAST Man Taught by Processes of Nature. 

 The sphinx of Egypt is nearly covered up 

 by the sand of the desert. The neck of the 

 sphinx is partly cut across, not, as I am 

 assured by Mr. Huxley, by ordinary weather- 

 ing, but by the eroding action of the fine 

 sand blown against it. In these cases Na- 

 ture furnishes us with hints which may be 

 taken advantage of in art; and this action 

 of sand has been recently turned to extraor- 

 dinary account in the United States. When 

 in Boston [1872] I was taken by my cour- 

 teous and helpful friend, Mr. Josiah Quin- 

 cey, to see the action of the sand-blast. A 

 kind of hopper containing fine silicious sand 

 was connected with a reservoir of com- 

 pressed air, the pressure being variable at 

 pleasure. The hopper ended in a long slit, 

 from which the sand was blown. A plate 

 of glass was placed beneath this slit and 

 caused to pass slowly under it; it came out 

 perfectly depolished, with a bright opales- 

 cent glimmer, such as could only be pro- 

 duced by the most careful grinding. Every 

 little particle of sand urged against the 

 glass, having all its energy concentrated 

 on the point of impact, formed there a little 

 pit, the depolished surface consisting of in- 

 numerable hollows of this description. 

 TYNDALL Fragments of Science, vol. i, ch. 

 7, p. 193. (A., 1897.) 



1758. INVENTION UNSUCCESSFUL 



Destructibility of Lava Artificial Stone 

 Lacks Endurance. Some years ago a very 

 ingenious invention was submitted to trial 

 in the works of the Messrs. Chance, of Bir- 

 mingham. It had been suggested that if 

 certain lavas of easy fusibility were melted 

 and poured into molds we might thus ob- 

 tain elaborately ornamented stonework, 

 composed of the hardest material, without 



the labor of the mason. The molten rock 

 when quickly cooled was found to assume 

 the form of a black glass, but when very 

 slowly cooled passed into a stony material. 

 Unfortunately, it was found that this ma- 

 terial did not withstand the weather like 

 ordinary building stones, and in conse- 

 quence the manufacture had to be aban- 

 doned. JUDD Volcanoes, ch. 3, p. 5. (A., 

 1899.) 



1759. INVENTIONS OF PRIMITIVE 

 MAN The Roller and the Pulley among Ameri- 

 can Aborigines. The roller I have found 

 certainly in two areas. The Eskimos, in 

 landing a heavily laden skin-boat, accord- 

 ing to Elliott, lay down on the beach, in a 

 row, inflated sealskins, used as floats with 

 their harpoons. Upon these the craft is 

 beached without the vexation of unloading 

 her. A moment's reflection will show that 

 in this apparatus the pneumatic tire is 

 foreshadowed. The other example of the 

 roller is the use made of it on the North 

 Pacific coast in moving the great logs 

 to be used in constructing the communal 

 houses. The pulley in its simplest form i* 

 described as an invention of tepee-dwelling 

 Indians of the plains. When the women 

 had set up the three chief poles of the tent, 

 the skin cover was hauled up by a line fast- 

 ened to the top margin, passed over the 

 fork of the poles above, and hauled by wom- 

 en at the other end. When the time came 

 to strike tent, the line was loosed and the 

 poles drawn together at their bases. Elliott, 

 however, figures a group of Eskimos landing 

 a huge walrus by means of a compound pul- 

 ley. A long, stout walrus line passes around 

 greasy pegs driven between the rocks and 

 through slits cut in the animal's hide. 

 MASON Aboriginal American Mechanics 

 (Memoirs of the International Congress of 

 Anthropology, p. 76). (Sch. P. C.) 



1760. INVESTIGATIpN, ORIGINAL 



The Mainspring of Technical Education. 

 At the present time there is a cry in Eng- 

 land for technical education, and it is a cry 

 in which the most commonplace intellect can 

 join, its necessity is so obvious. But there 

 is no cry for original investigation. Still 

 without this, as surely as the stream dwin- 

 dles when the spring dies, so surely will 

 " technical education " lose all force of 

 growth, all power of reproduction. Our 

 great investigators have given us sufficient 

 work for a time; but if their spirit die 

 out we shall find ourselves eventually in 

 the condition of those Chinese mentioned 

 by De Tocqueville, who, having forgotten 

 the scientific origin of what they did, were 

 at length compelled to copy without varia- 

 tion the inventions of an ancestry wiser than 

 themselves who had drawn their inspiration 

 direct from Nature. TYNDALL Lectures on 

 Light, p. 218. (A., 1898.) 



1761. INVESTIGATION, UNTIRING 

 SPIRIT OF, IN MONKEY Patient Industry 

 Evinced. In conclusion, I should say that 



