Sussex county, in the State of New Jersey, consists of
the following substances, according to Berthier and Thomson: Peroxide of
iron, 66; oxide of zinc, 17; sesqui-oxide of manganese, 16; total, 99.

* * * * *

A new adaptation of _Lithography_ to the process of printing in oil has
lately been invented by M. Kronheim of Paternoster-row, London. Hitherto
no strictly mechanical means have existed for successfully producing
copies of paintings, combining the colors and brilliant effects as well
as the outlines and shadings of the original. The ingenious invention of
Mr. Kronheim, while it enables him to supply copies of the great masters
wonderfully accurate in every respect, reduces the cost of such copies
to one-half the price of steel-engravings, and is a far more expeditious
process. The invention has reduced to a certainty the practice of a new
process by which the appreciation of art may be more widely extended,
and the works of great artists popularized.

* * * * *

THE ANNUAL OF SCIENTIFIC DISCOVERY, (published in Boston by Gould and
Lincoln), is an excellent abstract of all the chief movements and
discoveries in the scientific world for the year 1850. We advise all our
readers interested in any of the sciences to procure it, and its
companion volume for the previous year. The work will be continued, and
it will be invaluable as a library of facts and suggestions.

* * * * *

OXYGEN FROM ATMOSPHERIC AIR.--M. BOUSSINGAULT has recently obtained some
interesting results from his investigations in relation to oxygen. The
problem upon which he has been engaged was the extraction of oxygen gas,
in a state of purity and in a considerable quantity, from the azote in
the atmosphere. For this purpose, a preference was given to baryte,
owing to its property of remaining in oxygen of a moderate temperature,
and abandoning it under the influence of a heat sufficiently intense.
Ten kilogrammes of baryte, completely oxidized, were found able to take
and afterward return 730 litres of gas. This is the number indicated by
theory; for celerity of operation, more than 600 litres can be counted
on. In that limit, and in operating on 100 kilos. of matter, 6,000
litres of oxygen gas might be disengaged at each disoxidization; four or
five operations might be performed in 24 hours, which would thus furnish
from 24,000 to 30,000 litres of gas