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extensive and important iron works in this parish — when con- 

 nected with iron works, the produce of which bore such a 

 very high character, and always fetched such very high 

 prices in the market. The principle which he had to submit 

 to them bore on the determination of the different qualities 

 of the different numbers or kinds of cast iron and malleable 

 iron, as produced from the different ores in the neighbour- 

 hood. In order, however, to render the subject intelligible, 

 and the process satisfactory, he thought it would be useful to 

 develope in the outset the principles upon which the mode of 

 determining the qualities of the different substances were 

 founded ; for the methods of inductive science required that 

 they should, at all events, be enabled to see some relation 

 between the cause and the effect, the means and the end. 

 Thus to place in some measure before them the principles 

 connected with the mode of determining the qualities of iron 

 or steel, it would be necessary to state a few particulars with 

 respect to the nature of the magnetic principle on which the 

 determination depended. The magnetic principle, it should 

 be observed, was merely a secondary principle, and not a 

 principal agent. It was an attribute of one of the great 

 agencies which the Creator had appointed for subjecting the 

 material and physical creation to his will. They found that 

 all physical substances in nature were endued with certain 

 properties, and subjected to certain laws : as, for instance, 

 two particles of certain bodies, possessing variety but affinity 

 of nature, could not be brought together without combining, 

 nor, when united, without producing a total change in the 

 quality of the resulting substance. Thus, two substances, in 

 themselves acrid or corrosive separately, or each possessing 

 noxious properties, by being brought together might combine 

 and become harmless. In bringing them together there was 

 a certain mysterious agent engaged, of the original and 

 essential nature of which we are ignorant— only knowing 



