p. 17

-17-

1827.

the rock, which is more or less, according to the depth of the rocks and serves as a foundation and commencement of a pavement which extends to the top of the banks. This pavement is necessary to prevent the abrasion of the banks by the motion of the water produced by the wheels of steamboats, &c. The excavation of rock is done by drilling and blasting, and is afterwards raised from the canal by the use of a crane, of the same construction as those used on the mountain ridge of New York., invested by Mr. Orange Dibble. Of this crane I enclosure a figure. (Sketch -No. 4).

There are four locks, three lift locks, and one guard lock. They are all combined and situated at the lower end of the canal opposite Shippingsport. The guard lock is 190 feet long and 50 feet wide in the chamber. Its walls are 42 feet high, 13 feet thick on the bottom, and 5 at the top,-their upper ends are semi-circular with a radius of 13 feet. The three lift locks have a lift of about 9 feet each,- they are of the same dimensions in the chamber as the guard lock. Their walls are 20 feet high and 8 feet thick at the bottom and 3 feet at the top. The upper gates to these locks are sunk 4 feet below the canal, a lock above so that the water can be discharged through them to fill and empty the lock without inconvenience to passing boats. Culverts of sufficient size, through the walls in the canal way, would too much weaken them. At the time of the last annual report of the President and Directors, of the Louisville and Portland Canal Company, it was expected by them that the canal would have been completed by this time. But they have been disappointed as will be seen from the following statement.

Of the 687,000 cubic yards of earth 141, 000 yet remain to be excavated, ~44,000 is about the number of perches of mason work to be laid in the locks of which only 12,000 have been laid.