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NOTICES OF AUTHORS. 



lative to vegetation ; or, as it has been thought, by 

 the resting for a season. In the case of any tannin 

 or inert vegetable matter existing in the soil, the 

 heat and drying -^^ill tend to reduce these to a con- 

 dition suitable for vegetable food. In the West In- 

 dies, when a summer fallowing is resorted to in order 

 to get clear of the weeds, the fertility of the ground is 

 considerably lessened, from the evaporation or burn- 

 ing out of the putrescent or carbonaceous matter. 

 Were the fallo^^ing continued for several succes- 

 sive seasons, there is no doubt that the whole matter, 

 which, combined with earth, forms mould, would be 

 dissipated. 



About a c^ntmy ago, it was the practice, in our 

 neighbourhood (an alluvial clay district), to build up 

 the soil of the fallow division, furrow deep, into thin 

 dikes, or walls, about 5 feet high. This was done 

 in early summer. After being dried and aerated by 

 the summer's drought, the dikes were levelled do^Mi 

 in the autumn and sown with wheat. This system 

 was considered so fertilizing as to counterbalance 

 the labour and the loss of a crop. 



Om' own practice has proven that there is scarcely 

 any manm-e more effective for one crop, particularly 

 of spring sowing, than the clay of old mud walls of 



