134 BOARD OF AGRICULTURE. 



are related to the inorganic world, to the animal kingdom and 

 to man. 



I cannot omit to notice the fact, that the four elements that 

 make up the mass of organic beings are everywhere diffused in 

 the atmosphere. 



The riches are above us ; but the plants cannot take in riches 

 from the air, unless they find what they need in the soil to 

 form ash. They are like sick men at richly furnished tables — 

 they need a tonic, a stimulant. 



The first relation of plants that demands our attention is to 

 the earth and air. It is from both of these that the majority of 

 jDlants draw their support. The root, as though loving dark- 

 ness, plunges into the earth ; the branch with its leaves seeks the 

 light. This polarity of the tree is striking, appearing as soon 

 as the germ begins to develop. Both branch and root are 

 formed from cells of originally the same nature, for under 

 proper conditions the root may put forth buds and leaves, while 

 the branches, under the influence of darkness and moisture, 

 develop roots. But the welfare of the tree demands that there 

 should be this polarity, and here Ave find it, a portion plunging 

 into the earth to keep the plant in position, and furnish it with 

 those salts from the earth needed for its growth, and tlie oppo- 

 site portion just as plainly seeking the sun, light and air, having 

 a structure just fitted for its work. The root divides and sub- 

 divides, stretching far through the soil, gathering in its richness, 

 and the leaves give increased surface for sweeping the gases 

 from the air, and for preparing the crude materials for the use 

 of the plant. All the varied forms of leaves are such as to 

 favor radiation, and thus to condense the dews upon them. The 

 delicate but firm woody framework, like the vessel's spars, keeps 

 the soft tissues stretched in place, that abundant surface can be 

 secured with light weight. We cannot but admire that pro- 

 vision by which all wide-leaved trees in the northern zone, where 

 snow and ice abound, are prepared for the winter. Their leaves 

 appear as by magic in the spring, but the stem of every leaf has 

 its curious joint, so that when the summer is past and the leaf 

 becomes ripe or is killed by the frost, it drops from the tree, and 

 naked branches alone are exposed to the snow and ice and winds 

 of winter. Further south, wideleaved trees are evergreen, but 

 were they so in northern climes, with their present structure, 



