146 Observations on Combustion. 
Muhlenberg’s Carices. Remarks. 
56. C. acuta. Exactly ours. 
57. — caespitosa. Do.—A specimen named C. Oederi by some 
correspondent, is C. pallescens. 
58. Carex? lagopus. This is C. Fraseri, Sims, but is not con- 
sidered certainly a Carex by Muhlenberg. 
It is not with his Carices, but among the 
grasses in another volume of the Herba- 
rium, 1470. The leaves are radical, a 
foot long and an inch wide, and flat, like 
those of C. plantaginea, but without the 
appearance of a midrib, striate, with fine 
and stiff serratures. It was collected by 
Mr. Kinn of Philadelphia, in the Chero- 
kee country. Pursh called it Mapania 
sylvatica, Aubl., but he is supposed to 
have been mistaken. 
This comparison shows that several species are contained in the 
Herbarium, some of which were already described, which Dr. M. 
has not mentioned in his work on the Grasses. 
Art. XIX.—Observations on Combustion, and the powers concern- 
ed in that process ; by Samurt Morey. 
TO PROFESSOR SILLIMAN. 
Dear Sir.—Ir is now more than twenty years since I have been 
in the constant, I may say daily practice of making experiments on 
the decomposition of water, by mixing with its vapor that of spirits of 
Turpentine, and a great proportion of atmospheric air. In its de- 
composition by explosion, the object was to obtain, for mechanical 
purposes, a. new and first moving power that should be perfectly safe, 
and altogether lighter and cheaper than that from steam. With a 
muck less proportion of air, the object was to furnish a steady and 
pleasant flame like that from oil or gas ; in both of which objects I have 
succeeded. 
In the course of these experiments, I could never fail to admire 
the wonderful, simple and convenient manner, which nature has pro- 
