OF THE

FRANKLIN INSTITUTE

DEVOTED TO

SCIENCE AND THE MECHANIC ARTS

EDITED BY

MR. LOUIS E. LEVY, Chairman; Mr. EDWIN S. BALCH,
MR. JAMES CHRISTIE, DR. H. W. JAYNE,
MR. EDWARD H. SANBORN, Committee on Publica-
tions; with the Assistance of the Secretary of the Institute.

VOL. CLXVIII.-Nos. 1003-1008
(84th YEAR)

JULY-DECEMBER, 1909

PHILADELPHIA

Published by the Institute, at the Hall, 15 South Seventh Street.

of

The Journal of the

Franklin Institute

DEVOTED TO SCIENCE AND THE MECHANIC ARTS

EDITED BY

MR. LOUIS E. LEVY, Chairman; MR. EDWIN S. BALCH,

MR. JAMES CHRISTIE, DR. H. W. JAYNE,

MR. EDWARD H. SANBORN, Committee on Publica-

tions; with the Assistance of the Secretary of the Institute.

In Memoriam-Persifor Frazer, A.B., A.M.,

Proceedings of the Stated Meeting held Wednesday, June 16, 1909

Mining and Metallurgical Section:

Some Problems of Forestry. By Professor Leslie B. Seely

Mechanical and Engineering Section:

The Dirigible Balloon with Gyroscope Control. By Russell Thayer

Electrical Section:

No. 1

Improvement of Power-factor and Commutation Conditions in Single-phase Series

Abstract of Proceedings of the Stated Meeting held Wednesday, June 2, 1909

Notes and Comments:

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Address all business correspondence, remittances, etc., to The Actuary.

Editorial communications to The Secretary.

Entered at the Post-office at Philadelphia in accordance with Section 199 of the Postal Laws and Regulations.