COURSE OF

86748

CIVIL ENGINEERING,

COMPRISING

PLANE TRIGONOMETRY, SURVEYING, AND LEVELLING.

WITH THEIR APPLICATION TO THE CONSTRUCTION OF

COMMON ROADS, RAILWAYS, CANALS, HARBOURS, DOCKS, TUNNELS,
AQUEDUCTS, VIADUCTS, PIERS, WATER-WORKS, &c. ALSO,

A TREATISE ON THE IMPROVEMENT OF LAKES,
RIVERS, BOGS, MARSHES, &c. BY DRAINAGE,
EMBANKMENT, CULTIVATION, AND

IRRIGATION.

THE WHOLE BEING DESIGNED FOR THE USE OF ENGINEERING COLLEGES,
PRIVATE SCHOOLS, PRACTICAL ENGINEERS, LAND PROPRIETORS
AND AGENTS, COUNTY SURVEYORS, ETC.

BY JOHN GREGORY, Esq. C.E.

Author of the Philosophy and Practice of Arithmetic, Practical Geometry, Conic Sections,
Mensuration, Astronomy, Use of the Globes, Construction of Maps, &c. &c. .
And Resident Director of the College for Civil Engineering,
Mining, and Agriculture in Ireland,

VOL. !,

DUBLIN

SAMUEL J. MACHEN 8 D'OLIER-STREET.

LONDON: LONGMAN AND CO. WHITTAKER AND CO. SIMPKIN, MARSHALL AND CO.
HOULSTON AND STONEMAN, HAMILTON, ADAMS AND CO. WASHBOURNE. TILT
AND BOGUE. AND ALL BOOKSELLERS

MDCCCXLII,

UNIVERSIDAD CENTR

BIBLIOTECA

ANACULTAD DE JURISPRUDENCIA

WEALE.

JOHN DOWNES, PRINTER,

4. YORK-STREET.

ΤΟ

CHARLES WILLIAM HAMILTON, Esq., M.R.I.A., F.G.S., &c.

THIS VOLUME IS INSCRIBED

AS A TOKEN OF RESPECT AND ESTEEM,

BY

THE AUTHOR.

PREFACE.

THE want of a treatise of an elementary character, properly arranged, so as to answer the purpose of instruction, is, it is hoped, a sufficient apology for writing a new work on Engineering. The only treatise on this subject that accords with the plan the author has in view, is one by Mr. Mahan, Professor of Military and Civil Engineering in the Military Academy of the United States of America. This is a work of considerable merit, and would have superseded the necessity of ushering another into the engineering world, if it had treated amply enough of all the subjects it contains, and if it had not left untouched altogether, several of those branches so essential to the Surveyor and Engineer.

The acknowledged importance of any work, having for its object the improvement of young persons destined for a profession which now ranks amongst the most honorable and most useful that a gentleman can dedicate himself to, renders its publication of some importance, heightened by the anxiety at present existing in the public mind, respecting the improvement of the country in the various branches of Agriculture a subject which occupies a considerable portion of the present work.

At a period when the developement of the natural resources of Ireland has become a subject of anxious solicitude throughout the land-when agricultural and farming societies are being formed in almost every district, with a view to improve the condition of both landlord and tenant, whose interests ought to be at all times identical-when strenuous exertions