176 SEASIDE DIVINITY. 



of the sea-shore, laden with vital oxygen from 

 the tropics, are often known to restore to the 

 cheek of the invalid the bloom of health, lost 

 amidst the defective ventilation of the busy fac- 

 tory or the impure atmosphere of the crowded 

 city. 



The fluid taken up by the roots of plants or 

 absorbed by their leaves is as unfit to nourish or 

 promote growth, till exposed to the influence of the 

 atmosphere, as the blood of animals before it is 

 supplied with oxygen. The leaves are the lungs 

 or gills by which vegetables breathe. They are 

 the organs in which the crude juices of the plant 

 are elaborated by exposure to atmospheric in- 

 fluences, and so rendered capable of ministering 

 to the health, the growth, and the life of the 

 plant. 



An examination of the leaf proves how ad- 

 mirably it is adapted to the office it is intended 

 to perform. It consists of an extension of the 

 skin or cuticle of the plant into a flat expanded 

 surface, supported by a skeleton prolonged from 

 the wood of the stem or branch. Between the 

 upper and under cuticle of the leaf is a soft green 

 tissue, which on being examined by the microscope 

 is found to -consist of distinct cells packed to- 

 gether more closely near the upper surface than 

 the lower, where there appear to be many cavities 

 and spaces between them. 



The cuticle is furnished with what botanists 

 call stomata or mouths. These are apertures or 

 pores of an oval and sometimes circular form, 



