7 



when I add to this, that in more recent experiments, one 

 of the strongest irons in Yorkshire has been placed in the 

 scale of strength much below another iron, well known to 

 be no stronger, (both irons being made from the same coal 

 and ironstone, a fence only parting the mineral fields of each 

 work,) I am driven to the conclusion that the object of 

 the experiments in question has in a great measure been 

 defeated. There are, however, some experiments in them, 

 which may not have been affected in their results by these 

 circumstances, two of which I shall point out to your con- 

 sideration. 



The first will be that of iron from two works using the 

 same materials. 



Elsecar iron (cold blast) mean ratio of its strength... 1000 



Milton iron (hot blast) mean ratio of its strength ... 809 



Elsecar iron, mean ratio of power to resist impact ... 1000 



Milton ditto ditto ditto ... 858 



In this case the difference is really much greater than 

 appears on the face of these experiments, inasmuch as the 

 specimens of pig iron from the Milton Works were made with 

 the addition of a portion of the red hematite iron ore from 

 Ulverstone, for the express purpose of giving greater strength 

 to that iron, as was invariably done many years for the pur- 

 pose of making tin plate, and during the war for the casting 

 of cannon. 



The second circumstance is that where Mr. Fairbairn re- 

 ports on a trial of fifty sorts of iron, of which each bar* of 

 hot and cold blast iron was made of the same materials, and 

 under the same circumstances. 



Cold blast iron, with a load of 392 lbs. increased the deflection 



in 108 days from 1.786 to 1.843 inches. 

 Hot blast iron ditto... 1.891 to 1.966 ditto. 



* I take this to mean each pair of bars. 



