220 PRACTICAL AGRICULTURE. 



unlike it. Now, wherever the subsoil is different 

 from the surface, this gradual deepening of the fur- 

 row enables us to mix soils without the labor of trans- 

 portation. The farmer should carefully mark the 

 effect. If good, he should continue the practice. If 

 bad, he should investigate the cause. It might be 

 owing to protoxide of iron in the subsoil. Should the 

 subsoil be of a sickly yellow, when first turned up, 

 but afterwards turn to a reddish brown, he might con- 

 clude that such is the case ; and he might then add to 

 the soil a little lime, or a compost containing it, and 

 continue the process of deepening his soil ; or should 

 he deepen his furrows very gradually, this protoxide 

 of iron would cease to be hurtful, merely by exposure 

 to the air. v 



421. A deeply cultivated soil — one properly amend- 

 ed, if not originally good and well manured,"* is a lab- 

 oratory in operation — at work for the owner's benefit. 

 By means of the silica and alumina, its chief ingre- 

 dients, it affords a safe anchorage for his plants ; its 

 salts and organic matter supply them food ; and more 

 than this, it is at work^ drawing other food from above 

 and below. The subsoil sends up its treasures, and 

 the playful breezes pay it their contributions as they 

 pass. 



422. Such a soil, one perfected by diligence and 

 skill, is in alliance with the silent and often unob- 

 served but mighty powers of nature, for the farmer's 

 good. It gathers from above and below for his bene- 

 fit. It subsidizes the powers of nature in his behalf 



