Charles Shattuck Hill

“ The universal method of hauling boats on canals until very recent times has been animal power exerted through a tow-rope attachment to the boat. In China the hauling is done by men who walk along a tow-path on the bank and pull the boat after them; in most other countries this work is done by horses and mules. Various attempts have been made to substitute steam-power for hauling canal-boats, and such power is considerably used, but as yet no mechanical motive power can be said to have replaced animal power. ”

“ The bottom of the channel is always made flat; in soft ground the sides are made sloping, the angle of slope depending upon the stability of the material, being quite steep in firm materials and quite flat in unstable materials; and in rock the sides are made vertical or nearly so. The attempt is always made for the sake of economy of excavation to approach as nearly to a rectangular cross-section as the conditions will permit. When the canal passes through towns the sides are made vertical to save space and provide quays, retaining walls being used in soft ground to form vertical sides. ”

“ Between Rome and Syracuse, water is drawn from Cazenovia Lake and other reservoirs, while at Syracuse the Erie Canal supplies water to the Oswego Canal. Buffalo is 568 feet above the level of the Hudson at Albany, the difference being overcome by locks at various points. The canal has been immensely successful, contributing largely to the growth of New York, Buffalo, and intermediate places, and serving for many years as the great artery of passenger as well as freight traffic between the northeastern sections of the United States and the newly settled States of what was then the West. ”

“ The usual methods of transferring vessels from one level or reach of a canal to another one are by locks, inclines, or lifts. Of these three devices, the lock is the one most extensively employed. A lock is a masonry chamber built at the junction of the two reaches, the bottom of which is a continuation of the bottom of the lower reach and the top of which is at the same level as the banks of the upper reach. Structurally this chamber consists of two parallel masonry side walls, closed near each end by a pair of folding gates. ”

“ In a boat canal of small section, the plant required is small and simple, but in large ship-canal sections very large and powerful machinery and elaborate power plants supplying compressed air and electricity arc employed. In small canals soft-ground excavation is commonly performed by means of shovels and plows for loosening the material, and scrapers and carts for carrying it from the excavation. In larger canals this plant is increased by the addition of grading and excavating machines and steam-shovels loading into carts or cars hauled by horses or light locomotives. ”

“ A gate consists of two leaves, the swinging edges of which meet on the centre line of the chamber, but as each leaf is somewhat wider than half the width of the chamber, they do not form a straight diaphragm across the chamber when closed, but are shaped like a very flat letter V with its point projecting toward the upper level or reach. ”

“ This canal, 28 miles in length, was originally designed to carry the drainage of Chicago to the Mississippi instead of to Lake Michigan. It has a minimum depth of 22 feet, a width at the bottom of 160 feet, and a width at the top varying from 162 to 290 feet. The canal extends from the Chicago River in Chicago to Lockport, where it joins the Des Plaines River. It has been proposed to deepen this canal and also the Illinois and Mississippi rivers and construct locks so that barges and light-draught vessels could pass direct from the Great Lakes to the Gulf of Mexico. ”

“ This construction gives greater strength to resist the pressure of the water. The height between the bottom of the down reach and the bottom of the upper reach is called the lift of the lock. The practicable height of lift in lock construction is limited, and where great differences in level have to be overcome, a series or flight of locks built end to end is employed. ”

“ No further money for continuing the work was forthcoming, and in 1900 an investigation was set on foot to determine the cost and prepare plans for a much greater enlargement which would permit the use of 1000 to 1200 ton boats. ”