YORKSHIRE ALUM WORKS. Q^Q 



side of the heap, this however does not prevent the escape 

 of the gas in any degree, but it prevents the wind from 

 penetrating, and assists in preventing the calcined mine 

 from falling, by forming a kind of crust ail over the heap; 

 this crust is soon decomposed by the action of rain, &c. 



The form of the places for calcining the rock in is badly 

 calculated to prevent the escape of the sulphureous acid gas. 

 If the combustion was effected in a building of the shape 

 of a smelting furnace, immediately upon the whole of the 

 rock becoming ignited the openings might be closed, and 

 the gas preserved. 1 have ascertained by experiment, that 

 nearly one half of the sulphureous acid gas is expelled by 

 a red heat, continued for a considerable space of time. 



Every suggested improvement is considered as an inno- Difficulty of 

 vation by the illiterate, and it may be truly said, to be more impr'ovem^its 

 easy to remove mountains than long established prejudices; 

 the anxious manufacturer is seldom sufficiently master of 

 his works, so as to be able to turn the scale of long esta- 

 blished custom : and the most enlightened and scientific 

 methodb are entirely defeated, when trusted to the hands of 

 workmen to carry them into execution. 



How little melioration can be expected among a class of 

 people, where reason has never made any impression upon 

 the mind! I would hail the man as a true patriot, who 

 shall endeavour to disperse this cloud of darkness from the 

 human race. 



The sulphureous acid gas, by absorbing oxigen from the 

 atmosphere, is converted into sulphuric acid; this change is 

 effected by means of the oxide of iron contained in the 

 mine, and moisture. It would certainly be worth ascer- 

 taining by experiment, whether the oxide of iron combined 

 with sulphtir in burning would not yield sulphuric acid if 

 moistened with water. 



I am aware that iron has a greater affinity for oxigen than 

 sulphur has in the fire, but id the great scale of nature she 

 observes laws peculiar to herself: the affinities observed in 

 the salts of the ocean are contrary to the order they appear 

 in our tables, here, we find the small portion of sulphuric 

 acid united to the lime; instead of forming a union with 

 the soda, as might be inferred. Lime in found to decom- 

 pose 



