Mucellan ics. 3 ? 7 



not hitherto been announced as a production of this country. We 

 embrace the earliest opportunity to state that an unquestionable spe- 

 cimen has been just received from Ilon^ Judge Tappan of Steuben- 

 ville, and the following notice is from his letter, dated IVIay 15, 1S30. 

 "I make the spec. grav. of this combustible* 1.6. ' One and a 

 half miles west of Cambridge, Guernsey county, Ohio, near Grutn- 



I mon's tavern, a bed of the mineral was found cropping out (not long 



since); It has been penetrated about two feet vertically, but tlie 



i depth or thickness of the bed is not yet ascertained. It appears to 



extend, like our other coal beds, into the hill horizontally : it is so 

 compact and hard, as to be more difficult to quarry than our common 

 coal ; it makes in the grate a very clear light, and leaves less resid- 

 uum than our common coah I hope to be able to give you a correct 

 analysis of it before long/' 



We would suggest to our respected correspondent, that the speci- 

 men forwarded (which is sufficiently large to exhibit the characters) 

 corresponds, strikingly, with the cannel coal of England : like that, it 

 is black, has a conchoidal fracture, and a resinous lustre : it is com- 

 pact, with only a slight tendency to the slaty structure, and it is high- 

 ly inflammable, burning by mere contact of the blowpipe flame, with 

 a brilliant light. 



Its high specific gravity (1-6) is remarkable ; the cannel coal of 

 England being only 1.2 or 1.3, and even the anthracites of Pennsyl- 

 vania being but 1.55. 



From the fact that there is, according to the observations of Judge 

 Tappan, but httle residuum, it is probable that the high gravity (which 

 is very obvious even in a hand specimen,) is owing to the greater con- 

 densation of the carbon, which of course gives a superiority to this 

 coal. The discovery is very interesting, and we shall hope to receive 

 a fuller account before the appearance of our next number. 



15. Plumbago of Shtrhridge, Mass. — Numerous localiues of this 

 valuable mineral are known in the United States ; and we are grati- 

 fied to observe that it is obtained in large quantities and of an excel- 

 lent quality, at Sturbridge, in Massachusetts. A large mass now lies 

 l>efore us, which is very pure, soft and sub-crystalline in its structure. 

 The saw cuts it easily into any form, and it admits of a high polish. 



* Judge Tappan regards it as resembling both jet and cannel coal, but as bein^ 

 not exactly like either. 



Vol. XVIII._No. 2, 48 





