to pour in, as they still do, and on October 1st, 1909, a second list
of permissible explosives was issued, as follows:

“EXPLOSIVES CIRCULAR NO. 2.
“DEPARTMENT OF THE INTERIOR.
“United States Geological Survey.
“October 1, 1909.

“LIST OF PERMISSIBLE EXPLOSIVES.
“Tested prior to October 1, 1909.

“The following list of permissible explosives tested by the United
States Geological Survey at Pittsburg, Pa., is hereby published for
the benefit of operators, mine owners, mine inspectors, miners, and
others interested.

“The conditions and test requirements described in Explosives Circular
No. 1, issued under date of May 15, 1909, have been followed in all
subsequent tests.

“Subject to the provisions named below, a permissible explosive is
defined as an explosive which is in such condition that the chemical
and physical tests do not show any unfavorable results; which has
passed gas and dust gallery tests Nos. 1 and 3, as described in
circular No. 1; and of which, in test No. 4, 1½ pounds (680 grams) has
been fired into the mixture there described without causing ignition.

“_Permissible explosives tested prior to October 1, 1909._

“[Those reported in Explosives Circular No. 1 are marked *.]