HISTORY OF INLAND NAVIGATION.

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In whatever part of a canal business is intended to be carried on, therewill require to be a wharf, with sufficient space for loading and unload-ing goods, with warehouses, weighing-engines, and cranes, for the useof the trade ; and where this is extensive, a Basin is requisite, to accom-modate boats which wait to discharge their lading, without interruptingthe regular navigation on the canal.

The regular drainage of lands is often interrupted by the line of acanal; to remedy which the water-course is continued by a Culvert,which is a circular drain continued under the bed of the canal, coatedwith clay. As water cannot always be supplied in due quantities forthe use of a canal from the natural flow of rivers, &c. it becomes neces-sary to supply this deficiency from rivers, ponds, mines, &c. on a lowerlevel, by means of engines; and for this purpose, the most powerful isthe steam-engine.

Having now enumerated the several articles of most importance to beknown, 1 shall beg leave to conclude with one word of advice of generaluse ; which is, that all works for the use of canals should in all cases bebuilt in the most substantial and workman-like manner possible, and ofthe best materials and constructions ; for, in so doing, much future ex-pence and inconvenience will be avoided in repair , perhaps in rebuild-ing. Were it necessary, many recent misfortunes might be mentionedto this purpose : but these would appear invidious. In all cafes con-tracts should be made full and explicit with respectable persons, and suf-ficient prices allowed. These will most likely insure the several worksbeing properly performed ; not that it is prudent to rely entirely onthem : the workmen should be looked after, and the materials well exa-mined in the progress of the works, by careful and able inspectors.

IN DEX

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