114 Manufacture of Steel. 
Defects in the applications of chemical science to the subject of steel 
and iron. 
The various textures and qualities of iron and steel, probably in 
most cases, owe their differences to their combination with different 
foreign substances, or with the same foreign substances in different 
proportions. How happens it, sir, that this subject is so little under- 
$ ? Can it for a moment be believed that the powers of modern 
chemistry are inadequate to discover the nature of these combina- 
tions, and the means by which they may be effected, varied, modi- 
fied, or prevented at pleasure? When we see the chemist, almost 
without hope of reward, seizing with avidity on some new body just 
brought down from the skies, or up from the i recesses of nature, 
summoning to his aid all his powers of analysis and synthesis ; (I had 
almost said, of annihilation and reproduction,) dividing and subdi- 
viding it into all its chemical constituents ; ultimately detecting in it 
as the cause of its novelty, some thousandth of a grain of a substance 
hitherto unknown ; then operating upon this until he has determined 
its specific gravity, its chemical affinities, the ratio of its chemical 
combinations, and even measured the angles of its primitive particles, 
—I say, when we see all this refinement of investigation, so freely 
bestowed on bodies unknown in the arts,.is.it not surprising that the 
causes, which so essentially modify the properties of iron and steel, 
should still remain almost unknown ; and that the art of manufactur- 
ing them, which, of all others, should be based on chemical scienee, 
should still continue almost in the state of mere empyricism. 
Scintillation of steel—inflammation of gunpowder. 
You inquire, sir, if we have ever tried whether gunpowder will 
fire in the sparks from our polishing wheels.* We have tried the 
‘xperiment, and find that when coarse emery is used on the wheels, 
it will be fired at any distance to which the sparks extend ; but 
when very fine emery is used, a stream of innumerable sparks may 
be poured upon coarse gunpowder without inflaming it. The same 
powder, however, on being finely pulverized, will be readily inflamed 
a en Se Oe ee i oa 
* The polishing wheels referred to, are of various sizes and kinds, from large grind- 
stones on which the gun barrels are ground, to small wheels, covered with oiled 
eather and armed with emery powder ; all these wheels are moved with great ra- 
pidity by strong water power, and when the steel articl held upon them, there 
is a splendid corruscation of innumerable sparks flying off in tangent lines, which 
oe such rapidity, that the wheel is constantly surrounded with 
a fed. 
