426 On Metallic Minerals. 



They at first tried the fire-stone from Dumfries, but it 

 failed, so far, that it would only answer for lining. They 

 now obtain their fire-stone from the State of Ohio, of a 

 good quality. 



Moulding sand is obtained on the site of the furnace, and 

 it is considered good by several English moulders. 



Secondary limestone abounds in the neighbourhood con- 

 taining organic remains, and burning easily into excellent 

 lime. Fetid limestone is also met with. These limestones, 

 1 am inclined to believe, support the beds of sand, clay, 

 and boulders, in which the iron is disseminated, from which 

 the bog iron ore is derived. 



Mr. Harris says, that boulders abound all over the 

 London District, but that primary rocks have not been 

 observed in situ. 



Timber for charcoal is abundant and in great variety — 

 the hard maple is preferred. 



With respect to water, they have great advantages. — 

 Potter's Creek, although not a large, is a never-failing 

 stream. The works are situated at its entrance, imme- 

 diately on the siiore of Lake Erie. Hence the great 

 convenience of sending off their weighty manufactured 

 articles, or of receiving any supplies which they may 

 require, Aviihout the expense of land carriage. 



Mr. Harris closes his information by the following facts, 

 which may be interesting to future travellers. — " There is 

 a petroleum spring at Lobo, on the river Thames; and 

 there is a remarkable spring, in my creek, in Charlottc- 

 ville, near where I reside. 1 have frequently smelt the 

 vapours from this spring, at the distance of full half a milej 

 it deposits sulplnu- on the leaves, sticks, and stones, 

 jn the stream." 



