220 APPENDIX A. 



(to be proved). Thus heat is produced by motion. 

 If it is matter, it must be admitted that the matter 

 is created by motion. 



(2) When an air-pump is worked, and at the 

 same time air is admitted into the receiver, the 

 temperature remains constant in the receiver. It 

 remains constant on the outside. Consequently, 

 the air compressed by the pumps must rise in 

 temperature above the air outside, and it is ex- 

 pelled at a higher temperature. The air enters 

 then at a temperature of 10, for instance, and 

 leaves at another, 10 -f 90 or 100, for example. 

 Thus heat has been created by motion. 



(3) If the air in a reservoir is compressed, and at 

 the same time allowed to escape through a little 

 opening, there is by the compression elevation of 

 temperature, by the escape lowering of tempera- 

 ture (according to Gay-Lussac and Welter). The 

 air then enters at one side at one temperature and 

 escapes at the other side at a higher temperature, 

 from which follows the same conclusion as in the 

 preceding case. 



(Experiment to be made : To fit to a high-pres- 

 sure boiler a cock and a tube leading to it and empty- 

 ing into the atmosphere; to open the cock a little 

 way, and present a thermometer to the outlet of 

 the steam; to see if it remains at 100 or more; 



