Anthracite formation of Wilkesbarre, &c. i 
If the fire places are properly constructed for burning 
this coal, I am well convinced that most of the citizens of 
Philadelphia will give it a preference to wood. 
FREDERICK GRAFF, 
We, the undersigned, do certify, that we are now using 
the stone coal for heating hoops for cut nails, and find it 
10 exceed any other coal or wood fire for this purpose. 
Our practice is, in the morning when we leave the shop 
for breakfast, to throw a quantity of coal on the fires, which 
will be fit for working on our return, and will last until we 
leave it at nine in the evening, when we again put on a 
quantity which lasts until the next morning at breakfast 
time. We find a very great advantage in thus having the 
fire ready to work at an early hour in the morning. Such 
a fire requires about a half bushel of coal in twelve hours. 
We find also, that the hoops heat in half the time that 
they do with any other fire. 
Upon the whole, we think that the Lehigh Coal is much 
the best for nailing, and not attended with one fourth the 
trouble of any other fire, and that the nails are, in our opi- 
nion, superior to others on account of the quickness of the 
heat, which does not cause the iron to scale so much. 
We also cut one fourth more nails with this fire than with 
a wood fire. 
GEORGE SMITH. 
JOHN MORGAN. 
DANIEL COLKGLASER. 
December 7th, 1814. — 
I have used in my business for years past, occa- 
sionally, charcoal, sometimes Virginia coal, and at others 
Lehigh, and from use and careful examination of their rela- 
tive value, I am perfectly satisfied that one bushel of Lehigh 
coal is equal in durability and value to nearly three of 
Virginia, and from ten to twelve of charcoal; and further, 
I find that they are the only coal I can depend on for weld- 
ing of gun-barrels, as with them I am always sure of a true 
and uniform result. I have now used them twenty years, 
ahd would not be willing to be without them even if they 
cost me two dollars per bushel. 1 own three tilt hammers, 
and have worked for the United States and the state of 
Pennsylvania the last eight years. 
