96 MR. JOHN JUST ON FAULTS IN FARMING. 



that they have either to be converted directly into the 

 material of the crop itself, or act indirectly to the same ex- 

 tent in collecting it. The mode in which plants act upon 

 such material, and increase their growth by extracting 

 nourishment therefrom, is by drawing it in a fluid or gaseous 

 state, by means of the roots which run within the soil. Roots 

 in general, and particularly those of such plants as are cul- 

 tivated for agricultural purposes, are extremely and finely 

 branched or ramified, pushing out countless fibrils like gos- 

 samer threads, which insinuate themselves between every 

 particle of the soil, and fill every opening or interstice 

 wherein water can filter or air circulate. Each tip of these 

 countless fibrils wants a covering or rind, and consists of 

 numerous minute cellules or sacs, pervious like a sponge to 

 fluid, but wholly destitute of pores, through which any solid 

 particle however minute could introduce itself. Through 

 these tiny sponges the moisture within the soil, with what- 

 ever such moisture has dissolved, is being continually drawn 

 into the roots during the plant's growth, along with the fluid 

 air and such other gaseous constituents as may circulate 

 within the soil, or be liberated from sources of decomposition 

 -therein. The spongioles deliver what they absorb into 

 finely attenuated textures, and vessels constituting the main 

 mass of the roots ; such roots being there protected by a rind 

 or skin, which protects the ascending fluid from any contact 

 with the soil. Herein by their physical properties and vital 

 agencies, the vessels and tissues distribute the fluid through- 

 out the entire plant; such fluid, or as it is now called sap, 

 being acted upon by the various organs through which it 

 passes, until the whole it contains fitted for the growth and 

 structure of the plant has been extracted from it, and secret- 

 ed and stored up within the interior for the varied pur- 

 poses of its economy. Each change in the fluid's course 

 induces a movement. The superfluous fluid which conducts 

 such movements, is ultimately thrown ofl" by transpiration 



