424 On Metallic Minerals. 



tracted to supply the great and growing demand for their 

 manufactures. 



In 1830 the estahlishment was burnt by accident, but 

 was rebuilt almost immediately upon an extended scale 

 capable of doing more than double the work of the former. 

 In August, 1830, these works were again in full operation 

 under the firm of Messrs. Joseph and Benjamen Vannorman. 

 Mr. J. Vannorman by a simple and ingenious contrivance 

 has much improved the machinery of the blast, which now 

 consists of an overshot wheel, moving two pistons by a 

 single crank — the pistons being at right angles to each 

 other. But still this improvement does not, it is said, 

 produce that regularity of blast which is reqiiisite to extract 

 all the metal and turn out good work. So sensible are 

 they of this defect, that they save the slag to remelt, 

 although they have not yet done so, and probably will not, 

 unless the ore beds in the vicinity should fail, a circumstance 

 which is not likely to occur for some years, although 

 Mr. Harris says he is far from considering them as 

 inexhaustible. 



Mr. J. Vannorman has so improved these works, that 

 besides the articles previously mentioned, he has lately 

 succeeded in making some excellent mill castings of 

 large dimentions. 



Besides the furnace which I have mentioned, the same 

 firm has a forge in Woodhouse for making bar iron — not 

 of a very good quality. Mr. Harris writes thus: "the 

 best character 1 can give it is, an inferior cold short, but I 

 consider this inferiority to arise in great measure from the 

 defective mode of reducing the ore. The bar is not made 

 from pig iron, but from the ore, which is neither washed 

 or roasted, consequently good iron can hardly be expected. 



