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*' a considerable quantity, would destroy any acid in the coal. 

 " I first tried it upon some patches in a fallow field, which 

 " were sown with Wheat in 1826, and I thought I had been 

 " successful; but though the plants looked healthy during 

 " the winter and the spring, yet, towards the harvest, they 

 became shrivelled, and were not very productive. I re- 

 " peated the experiment the following year, again upon fal- 

 " low, but applying nearly double the quantity of lime ; and 

 " have been this year so fortunate as to reap as much wheat 

 " as from the other parts of the field, and the grass seeds 

 look better than on the adjoining parts. The patch was 

 very irregular, yet I may venture to estimate the quantity 

 of lime at about twenty cart loads per English acre, from 

 the kilns ; but I am convinced that I could scarcely apply 

 " too much, particularly as the coal is known to contain a 

 great quantity of sulphur, which, becoming acidified by 

 the action of heat and air, produces sulphuric and sul- 

 " phurous acid, the very poisonous efi*ects of which are ably 

 pointed out in your paper. I mean to follow up this 

 experiment, and hope to be able to convert to fertility 

 *' those barren places which are so very annoying to the eye 

 of the farmer, when they appear at harvest in fields other- 

 " wise covered with corn." 



Here, no doubt, there was an excess of acid, as the writer 

 conjectures, and the lime would have a chemical effect in 

 neutralizing that acid and forming sulphate of lime or 

 gypsum, which is a valuable assistant in agriculture ; and 

 thus the very property of the coal, which was considered 

 poisonous, was converted into nutriment. We have ourselves 

 experienced the good effects of applying to land the small 

 coke which is produced by riddling that which we supply to 

 the railway ; as our most promising crop of wheat is on a 

 field which was profusely dressed with that refuse. 



There are many other substances, hitherto considered of 



