88 Notice of new localities of Sahlite, Coccolite, &c. 
accidental defects or the concealment of the hinge upon 
what. he supposed to be the clypeaceous univalve, calyp- 
trea, (crag above London clay,) from Lake Superior, a 
cerithium (London clay,) from Lake Simcoe, an unio 
(cornbrash &c.) a mytilus, (coral rag, &c.) both from the 
north-east coast of Lake Huron; gryphea, (lias,) from 
Lakes superior and Simcoe, —arca, (lias,) Lake Simcoe, 
and Sanguinolaria. River Humber. L. Ontario. 
_ Note.—The explosion described by Dr. Bigsby in the preceding article 
p. 75 seems analagous to the natural fires mentioned by Prof. Dewey. p. 55. 
An intelligent farmer of Dover, Dutchess Co. N. Y. informed me that 
within the last 25 years he had several times seen a flame, many yards in 
height, issuing for some hours from the side of a mountain of mica-slate 
near his residence. The vegetables around were burned; and a strong 
sulphureous smell continued several days at the place. Many neighbours 
have witnessed this occurrence, which among the more superstitious has 
produced no little alarm. This occurrence has, in every instance, been 
noticed in the spring of the year, after a thaw, which favours the sugges- 
tion of Prof. Dewey that the inflammable gas is generated by the action 
of water with a metallic sulphuret. - Possibly Prof. Dewey alludes to 
this particular place. Sulphuret of iron is found here; and [ observed 
also a whilish efflorescence composed of acicular crystals of a salt, appa- 
rently aluminous, in cavities of the rocks. C. H. 
Art. II. Notice of new locatities of Sahlite—Augite—Cey- 
lanite, §c.—(Read before the NewsureH Lyceum, Feb. 
11, 1824. | 
Last November, thes Rev. I. Johnston, Baron Rederer 
and myself, visited, on a new geological excursion, a place 
called Greenwood Furnace, in Munroe, and about 18 or 
20 miles south of this place. About a half mile from the 
furnace, and near a smail stream which moves the ma- 
chinery of the works, we found large rocks of a very beau- 
tiful green coccolite and sahlite. The former varied in 
the size of its grains from that of a small shot to that of a 
filbert—they being uniformly of a laminated and highly 
crystalline structure, and easily submitting to mechanical 
division. On separating the grains, they generally pre- 
sented faces of crystals, more or less irregular, and indent- 
ed, except on the faces of the lamina, which were uni- 
formly plane. The appearance of the mass was much as we 
might suppose it would be, if it had been formed by shak- 
