562 ANNTTAL REPORT SMITHSONIAN INSTITUTION, 1916. 



5-foot lift. It furnishes a pool about 12 miles long, but at low 

 water vessels have difficulty in reaching the pool from the Ohio as, in 

 fact, is true of many of the tributary streams. This lock was built in 

 1895 and cost over $260,000. The maintenance charges during 1912 

 were $7,651, and tonnage handled that year was 1,187 tons. Since 

 1897 the maintenance has cost $86,398.97. The Green and Barren 

 Rivers likewise have canalized portions, providing 5-foot navigation 

 from the mouth in the Ohio to Bowling Green, Ky., and Mam- 

 moth Cave, a total distance of about 219 miles. The four old State 

 locks in Green River and the one in Barren River were purchased by 

 the United States in 1889 and restored to a condition for use, and 

 two new locks were built in Green River a few years later. No. 6, 

 the last of the series, was opened in 1906. The total cost has been 

 about $2,086,000, exclusive of the cost of the two new locks, and the 

 cost of maintenance in 1913 has been about $89,000. The freight has 

 been largely exchanged with Evansviile, Ind., which is a market for 

 the logs and ties which form the bulk of the traffic. Coal on Green 

 River forms the third important item of commerce. The commerce 

 at the lowest lock of this stream will not include some local business 

 which is carried on in the river above, but will include through 

 freight and will serve to indicate the change in commerce in this 

 stream from year to year. 

 Commerce, Lock No. 1 : 



Tons. 



1890 907, 146 



1895 344, 833 



1900 378, 684 



Tons. 



1905 466, 015 



1910 258, 199 



1913 302, 610 



Farther west the Cumberland and Tennessee Rivers empty into 

 the Ohio. The Tennessee is over 650 miles long and the Cumberland 

 518 miles. On both of these streams considerable new work has been 

 commenced within the last few years. The Cumberland has a series 

 of seven locks, extending from Lock A, 41 miles below Nashville, 

 upstream 166 miles, the last of which was finished in 1912, at a total 

 cost of $2,418,952 for all seven. Lock A, below Nashville, cost 

 $390,600, and Lock 21, near Burnside, Ky., which was built to pro- 

 vide a harbor at the headwaters of the river, cost $374,076. From 

 Nashville to the mouth of the river, 193 miles, no locks were built, 

 and the stream was in a very unsatisfactory state on account of shoals 

 during low-wat^er season. It was not until 1910 that the lower 

 section, connecting with the slack-water part already finished, was 

 provided for, at a cost of $3,165,000. This covered the cost of five 

 new concrete locks and dams. One lock, just below Nashville, known 

 as Lock A, had been finished in 1904, at a cost of $305,000. The 

 work on the five new locks is now imder construction (pi. 5, fig 2). 

 The locks are to be of concrete, with steel gates and fixed concrete 



