Chapter I: CHEMISTRY.--On the Different Modifications of Silver Bromide

and Silver Chloride.

Analysis of New Zealand Coal.

On the Determination of Manganese in Steel, Cast Iron,
Ferro-manganese, etc.

Manganese and its Uses.

Ozokerite or Earth-wax. By WILLIAM L. LAY. A valuable
and instructive paper read before the New York Academy of
Sciences.--Showing the nature, sources, and applications of this
remarkable product.

On the Constitution of the Natural Fats.