ON METALS FOR ORDNANCE. 



107 



Extracts from a letter from Mr. David Pilmore of Shoreliam, forwarded to 

 the Committee by Mr. John Mackinlay, dated Edinburgh, January 7, 

 1856. 



Mr. Pilmore considers that the inferiority of the iron of the present day 

 is due partly to the source from which it is derived, but chiefly to the manner 

 in which it is smelted. All the iron of the present day contains, according 

 to his statement, phosphuret of iron, amounting, even in the best gray sorts, 

 to ^ per cent. ; this salt being derived from the use of coal in smelting. He 

 thiniis also that the gunpowder of the present day may differ greatly in its 

 properties from that formerly manufactured. This difference he expects 

 from the fact that the charcoal now used in its manufacture is burnt in 

 closed iron vessels, thus preventing the passage of air through its tissues, 

 which was allowed formerly. 



Extracts from a letter addressed to Mr. Fairbairn by Mr. A. Handyside, 

 dated Derby, January 22, 1856. 



Mr. Handyside sends the annexed drawings of a mortar and cannon to 

 be made in parts ; the material to be wrought iron. 



The mortar (figs. 4 & 5) to be made of rings welded together, the whole 



Fig. 4. Fig. 5. 



Fig. 6. 



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to be turned and ground together and then firmly bound by longitudinal 

 bolts. The cannon (fig. 6) to be made in a similar way, the part behind 



