rated nitric acid;
afterward precipitating by means of water and washing the auric acid
until the liquor contained no trace of nitric acid. The auric acid
combines immediately with potash and soda. Mr. Fremy promises an
examination of the question whether gold is able, in combining with
oxygen, to form a salifiable base, as has been asserted. The present
experiment was undertaken mainly in reference to its use in
electro-gilding.

* * * * *

LIGHT AND HEAT.--Prof. Moigno lately presented to the French Academy a
memoir on the experiments of Neeft, in Frankfort, on the development of
_Light and Heat in the galvanic circuit_. M. Moigno witnessed these
experiments in person, and considers it proved, first, that light always
appears at the negative pole, and that this primitive light is
independent of combustion; second, that the source of the heat is
properly the positive poles, and that this heat is originally dark heat;
thirdly, that light and heat do not unite at the instant of evolution,
but only after the intensity of each has reached a certain point; from
this union ensue the phenomena of flame and combustion.

* * * * *

CHINESE COAL.--A late number of the Chinese Repository contains some
_notices of Coal in China_, by Dr. D. J. Macgowan, in which occur a
number of curious and interesting facts. Coal deposits are found to
exist throughout the mountain ranges which girt the great plain of
China; but unskilful mining and the difficulty of transportation enhance
its cost and limit the consumption, so that it is little used except for
culinary and manufacturing purposes. The best comes from Pingting-chau
in Shansi; the quality most in demand in central China is called the
Kwang coal, and is brought from various districts in Hunan. Numerous
varieties are produced in the province of Kiangsu--slaty, cannel,
bituminous and anthracite. This portion of the mineral wealth of China
is computed at nearly six millions of dollars. The scarcity of the
supply is owing not to the poverty of the mines, but chiefly to the want
of facilities for mining, which can alone be supplied by the
steam-engine.

* * * * *

WATER OF THE OCEAN.--The results of observations on the different
_Chemical Conditions of Water_, at the Surface of the Ocean and at the
Bottom, on Soundings, have been communicated by Mr. A. A. Hayes, State
Assayer of Massachuse