■4Ha 







Fig. 2. — Showing the effects of sterilized loam on the growth of lettuce. In the upper figure 

 are shown lettuce plants growing in uasterilizedloaui; in the lower, growing in the .same 

 loam sterilized. The difference in the average weight of these two crops, growing in the 

 same house and the .same soil, was 35 to 40 per cent. 



