Part I. Report of progress in 1869, by J. S. Newberry, chief geologist. Part II. Report of progress in the second district, by E. B. Andrews, assist. geologist. Part III. Report on geology of Montgomery County, by Edward Orton, assist. geologist.

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reached; but, on the contrary, it is confidently believed, by some metallurgists, that not many years will elapse till all our bar-iron is manufactured by some direct process. The ground of this confidence is the peculiar property that carbonic oxide has of reducing the oxide of iron at
a comparatively low temperature. If we put a few grains of pulverized
iron ore with some carbonaceous substance, in a test tube, and heat this
over a spirit lamp to a red heat-10000 or 1200~-the ore is immediately
decomposed, its oxygen uniting with the carbon, and grains of metallic
iron become visible. This is the theory of the Renton process, the
process of Dr. Smith, and what is known as Chenot's process, but up to
the present time all these methods have been practically unsuccessful,
from a difficulty in regulating the temperature; for it is a remarkable
fact that when the temperature is raised above 14000 fusion begins,
silicates are formed, and the mass is agglutinated together in such a way
as to be unmanageable, while the access of the gas to the ore is prevented. Several eminent metallurgists are, however, at work on this
problem, and it seems to me that their efforts must ultimately be crowned
with success. I need not dwell upon the benefits that would accrue to
society and civilization by a diminution of say one-half in the cost of
production of bar-iron. So great would be this benefit that there is
hardly a family in any civilized community who would not sensibly feel
it. As we have seen the great improvements that have taken place
within the last twenty years in the manufacture of cast iron have cheapened this material to half its former cost. On the other hand, the
Bessemer process has reduced the price of steel in an equal degree, and
now the cheapening of bar-iron has become the great metallurgic desideratum. It would be very strange if when the inventive faculty of our
people, combined with the experience of the world, are brought fully to
bear upon the problem that its successful solution should not be reached.
THE MANUFACTURE OF STEEL.
THE BESSEMER PROCESS.
Perhaps the best illustration of the progressive character of the iron
manufacture is furnished by recent improvements in the manufacture of
steel. It will be remembered that steel is iron with one per cent. of carbon, or cast iron from which three-fourths of the carbon have been
removed. Fifteen years ago all our steel was made by what is called the
" cementation process," so well known that I need not describe it. About
this time Mr. Bessemer, an English iron-master, conceived the plan of
forcing common air into melted pig.iron, and thus, by bringing its oxygen in contact with the carbon, to induce the formation of carbonic acid,
eliminate the carbon and produce malleable iron; or, by arresting the