OF

THE FRANKLIN INSTITUTE,

OF THE

State of Pennsylvania,

FOR THE

PROMOTION OF THE MECHANIC ARTS.

DEVOTED TO

MECHANICAL AND PHYSICAL SCIENCE, CIVIL ENGINEERING, THE ARTS
AND MANUFACTURES, AND THE RECORDING OF AMERICAN
AND OTHER PATENTED INVENTIONS.

EDITED BY

JOHN F. FRAZER,

Assisted by the Committee on Publications of the Franklin Institute.

COLLABORATORS.

For Mechanical and Physical Sciences.

ALEX. DALLAS BACHE, LL. D.
JOHN C. CRESSON, A. M.

THOMAS EWBANK,

JOHN GRISCOM, LL. D.

JOEL B. REYNOLDS, A. M.

RICHARD A. TILGHMAN, A. M.

B. H. BARTOL,

J. VAUGHAN MERRICK.

For Mining and Metallurgy.

RICHARD C. TAYLOR.
SAMUEL S. HALDEMAN,

For Engineering and Architecture.
THOMPSON S. BROWN, Civ. Eng.
WILLIAM H. EMORY, U. S. Top. Eng.
ELLWOOD MORRIS, Civ. Eng.

SOLOMON W. ROBERTS, Civ. Eng.
WILLIAM E. MORRIS, Civ. Eng.

GEORGE W. SMITH,

T. U. WALTER, Prof. Arch. Fr. Inst.

For Manufactures and Commerce.

JAMES C. BOOTH, A. M.
FREDERICK FRALEY.
SAMUEL V. MERRICK.
JOHN H. TOWNE.

Reporter of American Patents,

C. M. KELLER, late Examiner, Patent Office, Washington.

PUBLISHED BY THE FRANKLIN INSTITUTE, AT THEIR HALL.

1850

JOURNAL

OF

THE FRANKLIN INSTITUTE

OF THE STATE OF PENNSYLVANIA

FOR THE

PROMOTION OF THE MECHANIC ARTS.

JULY, 1850.

CIVIL ENGINEERING.

On the Motion of Water in Conduit Pipes; on Friction and Pressure in Pipes; and on Jets d'Eau. By M. D'AUBUISSON DE VOISINS, Ingénieur en chef Directeur au Corps Royal des Mines, &c., &c. Translated by T. HOWARD, for the Civil Engineer and Architect's Journal.*

[The Work, of which the present translation forms a part, must be considered as the most important and complete modern treatise on Hydraulic Engineering. In it the author has, with admirable clearness and precision, treated the entire question of the Motion of Fluids; and this in such a way as to render it equally inviting to the practical and the scientific man. The object of the translator is to supply a want which English engineers must long have felt-that of an intelligible explanation of the Motion of Water in Pipes; and in carrying out this object, he has considered it due to M. d'Aubuisson and the public to give the exact meaning of the author as literally as possible. On the same principle the original equations are given, as well as the same reduced for English feet; for though these reductions have been carefully made, more confidence will be felt in important calculations where both can be referred to. Unless otherwise expressed, the whole of the dimensions in the examples are understood to be in English feet, and the time in seconds.]

Similarity of the Motion in Pipes and in Canals.

1. In a long inclined pipe, as in a canal, water moves by virtue of its gravity or weight, or rather that part of its weight called into action by the

* From the London Civil Engineer and Architect's Journal, for April, 1850.

VOL. XX.-THIRD SERIES.-No. 1.-JULY, 1850.