106 THE HUMAN SIDE OF TREES 



nebuel of the trade world. In Sicily the natives 

 find a sugary gum exuding from the flowering ash 

 tree; they gather it with a knife in the same way 

 that children gather chewing-gum from the spruce 

 tree. There are similar exudations in the larch 

 tree. Some of these gums, especially the sugary 

 ones, are fairly nutritive. It is said that members 

 of lost caravans have more than once been saved 

 from starvation by eating gum contained in their 

 cargoes. 



Syrups, which are really thinner gums, are ex- 

 emplified by the common maple syrup, and also by 

 the sap of such smaller plants as the cane and the 

 corn. These, in various degrees of density and in 

 unlimited flavours, form valuable foods for human- 

 ity as well as numerous plants and animals. Trees 

 always manufacture the exact things they need; 

 man should remember that he is only one of na- 

 ture's wonders! 



All trees exhale oxygen or other gases; in the 

 tropics there is a gas tree with exquisite white flow- 

 ers, and tapering, candle-like branches. The exu- 

 dation of gas takes place in the form of vapour. 

 Another very interesting gas plant, the fraxinella, 

 exudes such quantities of gas that if it be protected 

 from the wind by means of a paper or sheets of 

 glass and a match applied, it immediately takes 



