The earth of the limestone caves of Tennessee, Alabama, Georgia,
Arkansas, and other States, was rich in nitrate of lime, and this salt
was convertible into saltpetre by lixiviation and saturating with the
lye of wood ashes. Some of these caves were personally visited, and
great efforts made to have them worked to full capacity. Agents were
sent out to investigate their capabilities with authority to make
contracts, and supply the necessary information for their working; the
last was accomplished by means of a pamphlet which I published in
Nashville giving detailed instructions, and which was distributed
throughout the country; it was republished in Richmond, New Orleans and
other places. As rapidly as the crude saltpetre was received from the
caves it was refined and sent to the powder mills, and the products
mostly sent to General A. S. Johnson's command. About 100,000 pounds of
gunpowder were thus supplied before the fall of Nashville, besides a
considerable amount sent to New Orleans and other places.

The caves of Arkansas were rich in nitrous earth, and those of Texas
still more so, and these supplied the armies west of the Mississippi
river with material for gunpowder. As early as practicable I sent out
instructed powder-makers to both those States, who under the directions
of the military authorities, assisted to put up the necessary powder
mills for the Trans-Mississippi department, which after the fall of
Nashville was left necessarily to its own resources.

In the early part of November my time had become so much occupied that
it was no longer practicable to attend to the production of saltpetre,
and Mr. F. H. Smith was sent from Richmond by the Chief of Ordnance to
relieve me from its duties. At a later day a separate department was
established, called the Nitre and Mining Bureau, which then had the
entire charge of its production.

In the latter part of November, by the desire of General Lovell--the
able officer in command at New Orleans--I proceeded to that city and
examined the temporary arrangements for making gunpowder, and also
conferred with him relative to procuring a supply of saltpetre from
abroad. He suggested the chartering of the steamship Tennessee, then
lying idle in the river near the city, to proceed at once to Liverpool
and take in a cargo of saltpetre and return to New Orleans, or, in case
of necessity, to put in at Charleston or Wilmington. The suggestion met
my views, and was approved