H. H. A., of N. Y.—The lining up of a beam engine, in a vessel, is a process for which no definite mode of procedure is exclusively applicable. It is an operation to which common sense and judgment must be brought, and for which each engineer must be a law unto himself.
J. S., of Va.—The use of horizontal propellers to force balloons up or down is not a new suggestion. It has been tried, but, we believe, without much practical success.
J. T .S., of N. Y.—You will find further information on the subject of transmitting power by compressed air, in our editorial columns of last week.
APPLICATIONS FOR EXTENSION OF PATENTS.
Harvesters.—William T. B. Read, Chicago, Ill., has petitioned for an extension of the above patent. Day of hearing, May 17, 1871.
Mode of Fastening Sheet Metal on Roofs, etc.—Asa Johnson, Brooklyn, N. Y., has petitioned for an extension of the above patent. Day of hearing, May 3, 1871.
Method of Printing in Colors.—Rosalie Croome, Brooklyn, N. Y., has petitioned for an extension of the above patent. Day of hearing, May 3, 1871.
Machinery for Compressing Gaseous Bodies.—William A. Royce, Newburgh, N. Y., has petitioned for an extension of the above patent. Day of hearing, May 10, 1871.