PREFACE.

cannot be dispensed with; moreover, the principles embraced by it are also thosepractised by other artificers, and deserve to be understood, if on that accountalone.

Masonry is another branch of artificer’s work necessary to be thoroughlyunderstood by the Civil Engineer . The construction of every variety of archand dome occupies several pages: while the mathematical calculations upon thestrength of stone, the eflects of thrust and pressure, are dilated upon in severalparts of the work. The examination of the qualities of the various stones used inconstruction, together with an analysis of them, has been also fully detailed fromparliamentary and other documents that may be relied upon. As a science themason’s art has not in this country been made sufficiently prominent, nor excitedsufficient interest to call forth a treatise on the subject; but a volume would benecessary to exhibit the varieties of construction, the skill displayed in overcomingthe many difficulties that arise, and the gradual progress of this highly importantbranch of the profession.

Stone Bridges, and the principles upon which they are constructed, should bethoroughly studied by the Hydraulic Engineer , as they embrace all the knowledgerequired for the formation of docks, harbours, piers, jetties, quays, &c. which areamong the most triumphant efforts of the engineer. Of the machinery inventedto aid these works, and for which we are indebted to the bridge-builders of the lastcentury, ample accounts have been given in that portion of the work devoted tomachinery. The stone bridges over the Thames at London are highly deservingof attention; they may be considered as the result of great study, and the bestexamples of the application of science to such structures.

Canals, though now superseded by Railways , ought not on that account to beentirely neglected : for should steam navigation be still further improved, it is notimprobable that the data which have occasioned their disuse may prove more favour-able for their future construction, and hence the principles which belong to theirformation should be thoroughly understood by the civil engineer, as there aremany localities where canals would have a decided preference over railways.

Draining and Embanking have from a very early period occupied the attentionof the government as well as individuals. To confine rivers withm their banks, anddraw off the surplus waters from the surface of the land, are not only benefitsconferred on agriculture, but on its cultivators, by rendering the atmosphere moresalubrious and agreeable. Towns and cities also require attention to their sewerage,and the cleansing of the streets; and several local acts of parliament have beenpassed to enable these objects to be carried into effect; but one grand compre-hensive view is still wanting for this to be thoroughly accomplished, and it willnever be attained until the united efforts of a number of engineers, well-instructedm Geology, shall suggest for every district the best means of attaining it.

Railroads have given an extraordinary impetus to the profession; but it is timethat the principles of tlieir construction should be better comprehended: the public,at whose expense these highly important works have been executed, having hithertogenerally preferred the mechanic to the artificer, as the director of the chief linesthat have been completed. The construction of a railroad requires a great combi-nation of talent before it can be brought to perfection. The selection of the countrythrough which it is to pass, the building of bridges and viaducts, laying downrails, &c., are even more important considerations than the locomotive engine,which draws vast loads along the line. We have already had numerous failures,where the arts of construction have been employed, and it is to be desired that theengineers entrusted with the expenditure of such vast sums as are embarked in thesespeculations would qualify themselves, at once to comprehend these arts, and topractise them beneficially.

Eke Principles of Proportion which regulate the quantity of material to be em-ployed - in the arts of construction should be diligently studied both by the Architectand the Civil Engineer . To this subject the author has devoted the most careful con-sideration, having measured a vast number of buildings of all ages, for the purposeof forming an opinion upon the difference of character expressed in the Doric ,Ionic , Byzantine , and Mediaeval styles. For economic purposes this enquiry isworthy of great attention, it being apparent that if an entire building or a portionin the Byzantine style be cubed, one part out. of twelve only is devoted to material;m St. George’s. Chapel, Windsor, two parts ; in the Chapter-House at Wells four ;