SPONTANEOUS COMBUSTION. 57 



A. Ignition produced by the action 

 of one uninflamed body on another. 



Q. Give an example of spontaneous combustion. 



A. Goods packed in a warehouse will 

 often catch fire of themselves ; especially 

 such goods as cotton, flax, hemp, rags, 

 &c. 



Q. Why do such GOODS sometimes CATCH 

 FIRE of themselves ? 



A. Because they are piled together in 

 very great masses in a damp state or place. 



Q. Why does this produce spontaneous com- 

 bustion ? 



A. The damp produces decay or the 

 decomposition of the goods, and the great 

 heat of the piled-up mass makes the 

 decaying goods Jerment. 



Q. How does this FERMENTATION produce 



COMBUSTION ? 



A. During fermentation, carbonic acid 

 gas is given off by the goods, a slow 

 combustion ensues, till at length the 

 whole pile bursts into flame. 



Q. Why is the HEAT of a LARGE MASS of 

 aoods GREATER than that of a smaller quantity ? 



A. Because compression squeezes out 



