Anthracite Coal of Rhode-Island. 93 
The fracture is a distinct thing. This is compact, if the 
division pass in any other direction than in that of the shistose 
, ppe 
mbes we observe in obsidian; the surface is otherwise very 
mooth. 
The. form of the fragments is generally wedge-shaped, 
with sharp edges, and the pieces are very irregular, no two 
being alike, although they have a general ye padi The 
fragments are shaped very much like those of gun-flint and 
obsidian, and they rarely approximate to cubes and prisms.* 
This coal is very brittle, and breaks in the furnace much more 
easily than the Rhode-Island coal. 
Composition of the Lehigh anthracite. 
Carbon 90.1 
Water 6.6 
Silex 1.2 
Alumin 
i.] 
Oxides of iron and manganese 0.2 
Loss 8 
100 
(Vanuxem.} 
Chemical characters. 
_ ‘The account of these properties was anticipated in the for- 
mer paper, and in my experiments, nats ae in this Journal 
‘in. 1823, It may be remembered, that J found the anthracite 
Sie a exe very poor pis ne of. gelvanion, while 
that of Island was a good one 
The difference arises, apparently, from the smaller quanti- 
ty of metal contained in the former. eas is apparent, also, 
in the light gray colour of the ashes of ve coal. 
These ashes are only slightly magnetic ; Aer the Schnyl- 
*In this respect, the Pennsylvania anthracite differs from that of Rhode- 
Istand. There is te 
is, for- -reason, 2 in the 8 = “ 
coal, » eee -imthe furnace ; it requires more care in putting , 
and th difficult to burn. I haye mentioned, in a preceding 
note, that the pa coal of the Rh ode-Itand aateenene urns | with ease, and 
rarely impedes the draft, if introduced when the fire is active. 
