99 



blast iron were made of the same materials, and undier the 

 same circumstances. Cold blast iron with a load of 392 lbs. 

 increased the deflection in 108 days from 1.786 to 1.84 inches. 

 Hot blast ditto, in the same number of days, from 1.891 to 

 1.966 inches. Cold blast iron, with a load of 448 lbs., con- 

 tinued to increase in deflection, and ultimately broke after 

 sustaining the weight thirty-five days. All the hot blast iron 

 bars broke in the act of loading them with the above weight 

 of 448 lbs. 



The third experiment was by Mr. Todd, of Leeds, made 

 between August, 1840, and February, 1841, and was ab- 

 stracted from a paper by that gentleman, read before this 

 Society at Leeds, in June, 1841. 



Breaking weight. 

 Cwt. Qr. 



Bierley pig iron No. 3. cold blast 25 2 



Elsecar ditto No. 3. ditto 24 0 



Low Moor ditto No. 3. ditto 23 2 



Summerlee (Scotch) ... No. 3. hot blast 17 2 



Level, Staffordshire No. 3. ditto 16 0 



Mixed pig iron, five-v 



parts Low Moor, one vNo. 3. cold blast 30 0 



part Elsecar j 



Mixed pig iron, five-| 



parts Bierley, one VNo. 3. ditto 33 0 



part Elsecar J 



Mixed pig iron, No. 3, equal parts— Bierley, 

 Elsecar, Low Moor, Staffordshire, (cylinder 

 iron in the market,) Level iron, and Sum- 

 merlee 



These irons were all supplied in the regular way of 

 business, without the makers knowing that such experiments 

 were intended. 



The fourth experiment was introduced in order to test the 

 relative strength of wrought iron, made from cold and hot 



20 2 



