56 OPEN AIR GKAPE CULTURE. 



exactly tlie reverse of wha,t they were before. In 

 trenching with a view to mixture and pulverization, 

 all that is necessary is to open, at one corner of the 

 plot, a trench or excavation of the desired depth, 3 

 or 4 feet broad, and 6 or 8 feet long. Then proceed 

 to fill the excavation from one end by working out a 

 similar onfe. In this way proceed across the piece to 

 be trenched, and then return, and so on in parallel 

 courses to the end of the plot, observing that the face 

 or position of the moved soil in the trench must 

 always be that of a slope, in order that whatever is 

 thrown there may be Jiiixed and not deposited in 

 regular layers as in the other case. To effect this 

 most completely, the operator should always stand in 

 the bottom of the trend i, and first picking down and 

 mixing the materials, from the solid side, should 

 next take them up with the shovel, and throw them 

 on the slope or face of the moved soil, keeping a dis- 

 tinct space of two or three feet between them. For 

 want of attention to this, in trenching new soils for 

 gardens and plantations, it may be truly said that 

 half the benefit derivable from the operation is lost." 

 A more expeditious method of mixing the soil, 

 and one which varies but slightly from the ordinary 

 system, consists in cutting down the bank in succes- 

 sive sections so as to produce theoretically a series of 

 layers of soil and subsoil, but in reality a most inti- 



