THE EARTH. 



all have equal obligations to Heaven. We con- 

 sume a part of it, for our own sustenance, while 

 we live ; and, when we die, our putrefying bodies 

 give back the supply, which, during life, we had 

 accumulated from the general mass. 



CHAPTER XX. 



OF WINDS, IRREGULAR AND REGULAR. 



WIND is a current of air. Experimental philo- 

 sophers produce an artificial wind, by an instru- 

 ment called an asolipile. This is nothing more 

 than a hollow copper ball, with a long pipe ; a 

 tea-kettle might be readily made into one, if it 

 were entirely closed at the lid, and the spout left 

 open ; through this spout it is to be filled with 

 water, and then set upon the fire, by which 

 means it produces a violent blast, like wind, 

 which continues while there is any water remain- 

 ing in the instrument. In this manner water is 

 converted into a rushing air; which, if caught 

 as it goes out, and left to cool, is again quickly 

 converted into its former element. Besides this, 

 as was mentioned in the former chapter, almost 

 every substance contains some portions of air. 

 Vegetables, or the bodies of animals left to pu- 

 trefy, produce it in a very copious manner. But 

 it is not only seen thus escaping from bodies, 

 but it may be very easily made to enter into them. 

 A quantity of air may be compressed into water, 



