A GREEN LEAF 



8 i 



is not all. These same atoms supply us and every 

 living animal, not only with pure air to breathe, 





Fig. 52. The epidermal tissue of a tulip leaf, showing 

 the " stomata" or breathing-pores and cells. 



but also with every particle of food that we con- 

 sume. And again, they supply us with innumer- 

 able comforts in our home life ; they provide 

 material which we utilise in the making of our 



