4 



>/ Bengal. [N.S., XII 



tion. With that extinct, the tribe might have to wait long 

 years or make long journeys to get a renewal. Even now, 

 amongst uncivilised races, men will prefer to visit a neighbour- 

 ing camp to replenish their extinct fire when matches have not 

 reached them. Imagination boggles at the invention of means^ 

 for restoring a fire de novo, and yet it is not the greatest step 

 in the " invention ' ' of fire as compared with its first utilisation. 



Several sources of natural fire, unstarted by man, are 

 to be found. There is the volcano always available, while 

 forest or prairie fires are spasmodic. In addition to the vol- 

 cano, in the ordinary and more popular sense, as a source of 

 fire, there are, as Mr. Coggin Brown has suggested, mud volcanoes 

 and similar eruptions also to be considered. From these, gas in 

 large quantities is often given off, and it very readily takes 

 fire. Whether the starting of flame is due to spontaneous 

 combustion, as occurs with certain compounds such as phos- 

 phoretted hydrogen, or to lightning, or to some hydro-electric 

 action, or to the impact of ejected stones, is not clear. The 

 fact remains that certain forms of natural gas do take fire 

 and often remain alight for years if the supply is continuous. 

 Natural fire would also from time to time be found in the 

 outcrop of coal seams or beds of peat under favourable circum- 

 stances. 



Forest fires are now generally due to man, but they occa- 

 sionally are originated by lightning, or possibly by friction 

 between dry branches waving in the wind, or by volcanic erup- 

 tions. Spontaneous combustion, such as occurs in stacks of 

 straw or hay, is an unlikely source of fire in nature, and there 

 are few recorded instance of man's adaptations of that pheno- 

 menon for useful purposes. Nor is it very likely that sparks 

 from a fall of rock would start a fire. Yet it is possible 

 that primitive man observed the frictional or spark origin and 

 adopted one or the other. Or again it is possible that he 

 noticed the warmth when rubbing two things together and, 

 by pushing the friction to a limit, obtained fire. 



Most people are inclined to give priority to the frictional 

 origin as opposed to a percussive origin, but now it is not 

 possible to decide with any certainty. Legendary lore will not 

 carry us back to the days of the mammoth, and so is absolutely 

 useless. The flint and steel is of course much easier to work 

 than the rubbing stick or the fire drill, but then iron and steel 

 were unknown. Sparks can be obtained with much difficulty 

 from properly chosen stones, such as pyrites or possibly from 

 carbonaceous grit as long as there is sufficient combustible 

 matter present to ignite in the highly heated particle which 

 flies off on impact. Ordinary stones, except perhaps with very 

 great violence, will not spark. On the other hand the fire 

 stick method is very difficult to work and is essentially a 

 matter of knack. How difficult it is, few people know, though 



