46 
of hot blast iron, so abundantly made in Scotland. Their 
success, however, must be doubtful so long as dreadful explo- 
sions of steam boilers, and extensive breakages of machinery, 
traceable to the use of that iron, continue so frequently to 
spread destruction and alarm. 
The Chairman wished to ask what was the difference in- 
volved in the question — was it the capacity of the iron to 
sustain weight, or its capability to take such fine impressions 
from the mould ? 
Mr. Hartop replied, its capability to sustain weight. It 
was strong iron only that could be used for forge purposes 
with effect. In the experiments made by Mr. Fairbairn of 
Manchester, the strength of the Byerley iron was placed very 
far indeed below that of I^ow Moor, — a circumstance 
which went the full length of showing that experiments in 
such matters, on a small scale, even when made with the 
careful attention Mr. Fairbairn had given to them, were 
liable to two objections. In the first place, there was great 
difficulty in obtaining a fair and proper quality of each iron 
to be experimented upon, in order to bring out a correct 
comparison between the various kinds of iron; and in the 
second place, the experiments in question were altogether at 
variance with the results of all practical experience on a large 
scale ; for it was a well known fact, that if there was any 
difference whatever between the irons of Low Moor and 
Byerley as to strength, it was rather in favour of the latter. 
There were many other circumstances tending to show the 
inferiority of iron made by hot blast, particularly the price 
in the market, which was the grand criterion of the value of 
any commodity. But he could adduce other facts in support 
of his position, and they need only go to Leeds, and inquire 
what had happened at Pottery-field, with which his friend 
Mr. Embleton would be acquainted. An engine of large 
power was put up there a short time ago, made at Bolton, in 
Lancashire, of hot blast iron. That engine broke, as well 
