THE 



POPULAR SCIENCE 

 MONTHLY. 



JULY, 1879. 

 WASTED FORCES * 



By WILLIAM H. WAUL, Ph.D. 



THOSE inventions are deserving of special honor, and generally 

 receive the most substantial recognition, which develop new in- 

 dustries or utilize waste products. 



The glycerine industry, which has attained colossal proportions, is 

 a notable illustration of a great manufacture based entirely upon the 

 saving of what until lately was a waste product of the soap-boiler. 

 As even more important, I may mention the industries connected with 

 the manufacture of aniline dyes and artificial madder from the refuse 

 coal-tar that was formerly the curse and nuisance of the gas-works. 

 Old boots and shoes and leather waste are turned to good account by 

 the chemical manufacturer in producing the cyanides, ferro and ferrid 

 cyanides, so indispensable in color-printing and photography. Of the 

 carcasses of slaughtered animals, not a scrap or morsel is allowed to 

 go to waste, as you are well aware ; and even the waste blood of the 

 abattoir is used by the sugar-refiner and the manufacturer of albumen. 

 Sawdust mixed with blood, or some other agglutinative substance, and 

 compressed by powerful pressure in heated dies, is formed into door- 

 knobs, hardware and furniture trimmings, buttons, and a thousand use- 

 ful and decorative articles ; or, as is the case with the spent bark of 

 the tanneries, it is utilized for fuel under steam-boilers. Oyster-shells, 

 of which our barbarous progenitors of ages ago made the shell-mounds 

 that delight the soul of the anthropologist of to-day, are burned to 

 lime ; the waste of the linseed-oil manufacturers is eagerly sought 

 after as food for cattle ; the waste ashes of wood-fires are leached for 

 potash ; river-mud is mingled with chalk, and burned and ground to 



* An address delivered at the opening of the spring course of lectures of the Wagner 

 Free Institute of Science, Philadelphia, March 1, 1879. 

 vol. xv. 19 



