22 Imperfections of our present processes. 



coveries fraught with such momentous consequences 

 as those of magnetism or of galvanism and electro- 

 magnetism, will be made very often. The progress 

 of scientific discovery is gradual ; we have at present 

 but mere glimpses of the new world of truth which 

 is being revealed to us by means of research ; we 

 are only at the very commencement of a knowledge 

 of the inherent properties of matter and its forces, 

 and consequently the methods we employ to utilize 

 them are extremely imperfect. Matter has a general 

 property of subdividing and transmuting forces ; if 

 we apply one force to a substance or machine, it 

 produces many effects, not only those we want, but 

 those also we do not want ; when we heat a piece of 

 iron, the heat produces a number of changes, 

 mechanical, electric, magnetic, and chemical, and 

 it is partly by means of what is termed the "internal 

 resistance " of bodies that these effects are produced, 

 and we know but little of that property. The ex- 

 plosive action in a gas engine produces not only the 

 mechanical force we desire, but also a quantity of 

 heat we do not want, and at a cost of a portion of 

 the gas. In a similar manner, in the steam-engine 

 the largest portion of the heat of the coal is con- 

 verted into forces which are lost; a large amount 

 of it is uselessly expended in warming the 

 machine itself and the surrounding atmosphere ; 

 much also is lost by friction. 



tThat "knowledge is power" is an old maxim, but 

 hat new knowledge is new power is a new maxim 



