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 This is a work of considerable merit, and would have superseded the necessity of ushering another into the engineering world, if it had treated amply enough of all the subjects it contains, and if it had not left untouched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 aves sowie for the encouragement of native arts and manufacwhen out University is extending the sphere of its 2 by having recently established a professorship of $ caring when a new College of Civil Engineering, AgriAnak, mund Mining, calculated to confer national benefit, by sawing up a new class of men, to explore the hidden treaÞace of an island, rich in soil, manes, and minerals, peculiar da geological formation, and favourably situated as regards Kommeprial intercourse with the etter countries-when the famation of railroads dlirong! be kadom is engrossing the wilcubion of the legislature, & weasur, de oudly to be desired, a la luge sminantly owlendared to nation penerally, by giving empl, Jubercomso, and by the scorev Ame and sparo, dowwing the mos by the autobivis of the my X min pinigdy's on the pvo; St Inland wat bestald W. N、 of the bimolim dos av V my v the condition of the wet... facilitating internal af steam, which annihilates temes azmeultural districts ber extensive in.provements and elsewhere, by which at greatest length e other, and vast when an English of bog and aremmerate ling companies of the different subjects of which it treats, simplified and arranged in such a manner as to afford much assistance not only to the learner, but to those practical engineers, also, whose practice has been confined but to few branches of the profession. To save the expense of purchasing a separate work on Trigonometry, and to render the following course as complete as the limits of the work would admit-a treatise on Plane Trigonometry is prefixed, containing such practical rules and examples as are of most frequent occurrence in the practice of engineering and surveying. This part of the work is succeeded by a survey by the chain only, as practised on the parish survey of England, communicated by Mr. George Gregory, C.E., Professor of Field Engineering in the College for Civil Engineering, Mining, and Agriculture in Ireland, who was engaged in that service. After which is introduced, the method of surveying estates trigonometrically, as illustrated in a survey of Her Majesty's Phoenix Park, in the year 1837, by the author's son, under his own immediate superintendence. The application of this method is extended to the surveying of extensive countries, as practised on the national surveys of England, Ireland, and France. Maritime and Subterraneous Surveying occupies a small portion of the work; and though the author discourages the use of the common circumferentor, as a surveying instrument, yet as it is still in such general use among surveyors, he has deemed it right to show how to perform a survey by it. Ample instructions are given for plotting a survey and calculating its contents, by different methods; also for copying, enlarging, and diminishing maps, with the description and use of the various instruments employed by surveyors, and the most approved method of adjusting them. The First Volume concludes with a few questions, introduced with a view to exercise the pupil in the preceding part of the work. The Second Volume commences with a treatise on levelling; after which is introduced the method of making and repairing turnpike roads, on the most improved principles; together with the construction of railroads, canals, harbours, tunnels, aqueducts, viaducts, &c., and a description of the atmospheric railway; concluding with the method of improving lakes, bogs, marshes, rivers, &c. by drainage, embankment, and cultivation. Interspersed through the work, especially the Second Volume, will be found a great variety of subjects connected with engineering-such as water-works, animal power, &c. &c.; also a variety of tables and formulas, useful to the practical surveyor and engineer; with the method of adjusting and using all the instruments required in the profession of engineering. Such is a slight sketch of the contents of a work, which its author confidently hopes will prove an acceptable and useful companion to the young engineer; while he trusts that the more advanced practitioner may also find it a compendious and easy book of reference; and that both will find in it a great deal of indispensable information, conveyed in a method such as to obviate the necessity of having recourse to other and expensive works upon practical science. |