374 Proceedings of Scientific Societies. 
No. Locality. > Carbon. Volatile matter. Ash. 
13. Tioga, - at 725 175 .100 
14. Cumberland, Md.,_ - - - “754 .170 .076 
15. Black Spring Gap. Grey vein, .860 045 .0S5 
A comparison between the coals of Cumberland, Md., Bloss- 
burg, Penn., Dauphin Co., Penn. and South Wales, shows a re- 
markable similarity of composition as respects volatile matter. 
The greatest difference, in fact, scarcely exceeds one half of one 
per cent, as will be seen by the following table. 
Carbon. Volatile matter. Ash. 
Cumberland, = -. - - - 754 170 076 
Blossburg, or Tioga, Hts - 725 75 100 
Dauphin, ~ - 761 169 ~—-.070 
South Wales, Dowlais, (by Berthier,) .795 175 — .080 
Philadelphia, Dec. 1, 1840. 
tal 
Art. XIU.—Proceedings of Scientific Societies. 
I. American Philosophical Society. 
Nov. 6, 1840.—Professor Bache submitted to the Society a Chart, rep- 
resenting the extraordinary variations of the magnetic declination during 
the term day, on the 29th of May last, prepared by W. C. Bond, Esq., from 
the observations at the Magnetic Observatory at Cambridge. 
Professor Bache read an extract of a letter from Lieut. Riddell, diree- 
tor of the Magnetic Observatory at Toronto, U. C., which stated that an 
entire discordance had been found between the curve representing the 
changes of inclination, on the February magnetic term day, at Toronto, 
Dublin, Brussels, and Prague, whilst those at the last three named stations 
agreed very well together. This result, Professor B. stated, confirms the 
conclusions previously drawn from the observations at short intervals, of 
Prof. Lloyd and himself, in November last. 
Mr. Walker made some observations in relation to the Observatory of 
the Harvard University, Cambridge, and stated that extensive arrange 
ments had been made, and were in contemplation, for prosecuting mag- 
netic observations and practical astronomy. 
Professor Bache made a verbal communication of some recent deter- 
minations of the magnetic dip, made by him at Philadelphia and Bal- 
timore. . 
He reminded the society, that on a former occasion he had submitted 
a comparison of the observations for magnetic dip at various stations, com 
mon to the series of Prof. Loomis, (Am. Philos. Soc. Trans Vol. VI, 
