276 HISTORY OF OHIO. 



mitting boats seventy-eight feet in length, and fourteen feet 

 ten inches in breadth, to pass freely through. 



Aqueducts are constructed with wooden trunks, supported 

 by piers of stone masonry, which, on the Ohio canal, with the 

 exception of two small structures in the Cuyahoga valley, is 

 of the same character as that used in the locks. The mason- 

 ry of the others is of uncut, or hammer dresssed stone. 



The stone culverts on the Ohio canal, with the exception of 

 a few of a small class, erected soon after the commencement 

 of the work, are composed of arches, formed of stone, cut in reg- 

 ular segments, and laid in range work, with wing and parapet 

 walls of cut stone. Those on the Miami canal, and a few on 

 the Ohio canal, are composed of rough or uncut stone. 



Wood culverts are used for land drains, and to pass small 

 spring runs under the canal, in situations where they will al- 

 ways be kept under water, so as not to be liable to decay. 



Large aqueducts and culverts, as well as dams, are found- 

 ed on piles, except where rock or other secure foundations 

 could be had. 



Where it has been found necessary to erect locks, in situa- 

 tions where the earth at the bottom of the pit was composed 

 of light alluvion, mud, or quicksand, bearing piles have in 

 some instances been used to form a secure and firm founda- 

 tion. But mature reflection, confirmed by numerous experi- 

 ments, has produced the conviction that a more secure, as well 

 as more cheap foundation can be obtained by excavating the 

 pit to an extra depth, and covering it with a stratum of coarse 

 gravel of from one to two feet in thickness, wrought into 

 puddle, in which the floor timbers are to be imbedded. This 

 plan has therefore, in most instances, been adopted. 



The Ohio and Erie canal, extending from the Ohio river at 

 Portsmouth, to Cleveland on lake Erie, was finished in 1831-2. 

 It is three hundred and nine miles long. 



This main canal has many other canals connected with it. 

 The side cut, leading from Lockburn to Columbus is eleven 

 miles in length. Ascending the main canal to Carrolton, a side 

 cut canal, now finished to Lancaster, is making to the falls of 



