SECT. XXXIV. CONSERVATION OF FORCE. 353 



a change takes place in the temper of glass under the influence of 

 powerful magnetism. 



Even from the limited view of the powers of nature which pre- 

 cedes, it is evident that the progress of science based upon experi- 

 ment tends to show that the various forces of light, heat, motion, 

 chemical affinity, electricity, and magnetism will ultimately be 

 traced to one common origin ; that they are so directly related, and 

 mutually dependent, that they are convertible, motion producing 

 heat, and heat motion ; chemical affinity producing electricity, 

 and electricity chemical action, &c., each mediately or immedi- 

 ately producing the other. These forces are transmitted through 

 substances ; they act upon matter, causing changes in the mole- 

 cular structure of bodies either momentary or permanent, and 

 reciprocally the changes indicate the action of these forces. Matter 

 and force are only known to us as manifestations of Almighty 

 power : we are assured that we can neither create nor destroy 

 them that their amount is the same now as in the beginning. 

 In chemical attraction the powers with which a molecule of 

 matter is endowed, and which give rise to various qualities, 

 never change ; even when passing through a thousand combina- 

 tions, the molecule and its power are ever the same. 



Machinery does not create force ; it only enables us to turn the 

 forces of nature to the best advantage ; it is by the force of wind 

 or falling water that our corn is ground, and the steam engine 

 owes its power to the force of heat and chemical action. As 

 force cannot be created, neither can it be annihilated: It may 

 be dispersed in various directions, and subdivided so as to be- 

 come evanescent to our perceptions ; it may be balanced so as 

 to be in abeyance, or become potential as in static electricity ; but 

 the instant the impediment is removed the force is manifested by 

 motion ; it may also be turned into heat by friction, but it is 

 never lost. Every motion we make, every breath, every word we 

 utter, is a force that produces pulsations which are communicated 

 to continually increasing particles of air, and conveyed through 

 countless channels so as to become indeed imperceptible to our 

 senses, yet they are demonstrated to exist as witnesses of the 

 words we have spoken or the actions we have performed, by 

 analysis, that all-powerful instrument of human reason.* 



* Babbage. 



