Explosives Testing Station at Pittsburg, Pa., in gas and dust gallery
No. 1. The charge of explosive to be fired in tests 1, 2, and 3 shall
be equal in disruptive power to one-half pound (227 grams) of 40 per
cent. nitroglycerin dynamite in its original wrapper, of the following
formula:

Nitroglycerin 40
Nitrate of sodium 44
Wood pulp 15
Calcium carbonate 1
---
100

“Each charge shall be fired with an electric fuse of sufficient power
to completely detonate or explode the charge, as recommended by the
manufacturer. The explosive must be in such condition that the
chemical and physical tests do not show any unfavorable results. The
explosives in which the charge used is less than 100 grams (0.22
pound) will be weighed in tinfoil without the original wrapper.

“The dust used in tests 2, 3, and 4 will be of the same degree of
fineness and taken from one mine.[6]

[Footnote 6: With a view to obtaining a dust of uniform purity and
inflammability.]

“TEST 1.--Ten shots with the charge as described above, in its
original wrapper, shall be fired, each with 1 pound of clay tamping,
at a gallery temperature of 77° F., into a mixture of gas and air
containing 8 per cent. of methane and ethane. An explosive will pass