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injure the tenacity, the links will be liable to break where 
the welding exists. Other iron may be strong to resist 
impact, or sharp blows, and stiff, — such would make good 
axletrees ; but unless it will turn well, free from asperities 
and black specks, termed greys, it is not approved. These 
greys are in reality very minute cavities ; their perfect absence 
it is very difficult to attain ; when attained, the iron is termed 
perfectly clear, and fetches a high price. If hard, it will be 
in request for all articles where a high polish, combined with 
stiffness and strength, is required ; if soft, for objects requir- 
ing tenacity. Iron, soft and extremely tenacious, by which 
I mean that which will bear much bending backwards and 
forwards, and a great strain, without breaking, is also much 
esteemed for peculiar purposes, such as for the harpoons 
used in the capture of whales. Independent of the quality 
of the iron after it has been fabricated into the article to be 
used, it is highly important that it should bear the fabrication 
into such article with as little liability as possible to be spoiled 
in the process. A smith will say that such and such iron is 
cold short, or red short, or that it is unsound, or that it 
will not weld, or that it will not punch, or that it is full of 
dirt, or that, if drawn to a point, it becomes brittle. I 
will explain a little further some of these defects. When a 
smith puts a piece of bar iron into his smithy fire, he fre- 
quently heats it to a white heat, and then begins fashioning 
the article he is making ; as he continues hammering, punch- 
ing, and bending the iron, it assumes by degrees a yellow, 
and then a red heat. If the iron be red short, the moment 
it turns red, if the smith attempt to punch or bend it, the 
iron cracks, and bis work is spoiled. Therefore, in working 
red short iron he is obliged to watch the colour carefully, 
and to suspend his work before it turns red, and to put it 
into the fire to re-heat it. This occasions a loss of time and 
greater consumption of fuel, and consequently increases the 
expense of manufacture. The usual mode of trying whether 
