Ill 



of the land in England is of this nature, especially in the 

 coal districts. A stiff soil is much more capable of per- 

 manent improvement by assiduous cultivation than a light 

 one, and it is to land of this nature that we must look for 

 the increased production which is necessary for the prosperity 

 of the agriculturist. 



Engine ashes are frequently considered as a nuisance, but, 

 when riddled, the smaller part may be usefully employed as a 

 top dressing to heavy stiff land, while the larger portion acts 

 well as a filling for drains. In two instances (one of them in 

 consequence of my own recommendation) I know them to 

 have thoroughly answered for the latter purpose, and the 

 drains are very effective. The larger portion of the burnt 

 coal-pit refuse would no doubt answer equally well. On the 

 table is some of the mineral water before alluded to, which is 

 remarkable for the quantity of sulphuric acid which it con- 

 tains, partly combined with iron : the presence of both can 

 easily be manifested — the iron, by applying ferro-prussiate 

 of potash, and the sulphuric acid with nitrate of baryta. 

 From the quantity of acid which is perceptible, part of 

 which is free or uncombined, I conceive it may be used as a 

 substitute for the sulphuric acid of the manufacturer, or for 

 gypsum, in fixing ammonia, and I have so applied it. May 

 it not also be used beneficially in the slacking of lime, by 

 which gypsum would be formed ? Sir Humphry Davy, in 

 his lectures, says : — " I have witnessed the fertilizing effects 

 " of a ferruginous water used for irrigating a grass meadow, 

 " near Woburn : I have no doubt the vitriolic water acted 

 " chiefly by producing gypsum." Wherever coal is much 

 impregnated with sulphuret of iron or pyrites, on exposure 

 to the weather, the water draining from it will be, more or 

 less, found of a similar quality. [A Salt, obtained by the 

 evaporation of this water, was on the table.] 



At a colliery, there are generally large accumulations of 



