ARBORICULTURE. 



241 



the river flows. And the same force of 

 flowing water, if properly guided, and 

 aided 'by modern dredging machinery, 

 will cut the channel to proper depth, and 

 maintain it there, giving the desired 

 depth of water for river navigation. 



RIVER BARS. 



The limestone ledges extending entire- 

 ly across the river bed are softer in 

 places than others, and more easily dis- 

 integrated. 



In such places the bed is deeper than 

 where the stone is of greater hardness. 

 Thus there may be spaces of several 

 miles extent where the low-water depth 

 is ample for all navigation purposes. 

 But where these harder strata still re- 

 main, the ledges form an obstruction, 

 around which, usually in the eddies, the 

 gravel and sand accumulate, and in 

 places bars are formed often a mile or 

 two in length and half to three-quarters 

 of a mile in width, flat, and raised but a 

 few feet above the surface of the waters 

 flowing in the channel. 



In order to control the low-water 

 gauge, the stream must be confined by 

 dredging, blasting out the rock ledges to 

 facilitate the scouring operation of the 

 current. 



THE^ QUEEN CITY, CINCINNATI. 



The city of Cincinnati, like Rome, is 

 situated upon many hills, and for the 

 most part is from one to three hundred 

 feet above the highest flood of the Ohio. 

 Yet there are many business houses 

 which occupy that portion of the city 

 which lies near the river ; this, many 

 years ago, having been the business heart 

 of the cit^^ Yet all the coal business, 

 numerous extensive coal yards and land- 

 ings must of necessity be upon the river 

 margin. Many of the largest manufac- 



tories also are located within the flood- 

 ed area. Tlie principal depots, both pas- 

 senger and freight, are in this portion 

 O'f the city and were surrounded by wa- 

 ter, shutting ofif nearly all trains and 

 stopping freight traffic for several days. 



The money loss from destruction and 

 injury to merchandise which could not 

 be moved was quite considerable, while 

 the losses to manufacturers are always 

 great when high water occurs. 



Laboring men, dependent upon the 

 constant daily income, invariably sufifer, 

 as their source O'f income is totally cut 

 ofif so long as the water remains in the 

 factories, or stops transportation to and 

 from their place of labor ; while the rail- 

 way companies are very heavy losers, 

 and must be at great expense in trying 

 to maintain traffic relations. Besides, 

 the many thousand's of business men and 

 citizens throughout the entire country are 

 inconvenienced, and suffer losses from 

 the stopping of traffic, delays, and in- 

 jury to freight in transit. 



Upou the other hand, there are numer- 

 ous persons along the Ohio River who 

 are lo'udly demanding a nine-foot stage 

 of water, with dams, locks, and slack- 

 water navigation, in order that steam- 

 boat traffic may be continued during the 

 low-water stage of the river. 



Owing to causes which are fully ex- 

 ]3lained in Practical ArboricuUnre, pages 

 26 to ^2, the depth of water varies very 

 greatly, often in midsummer being as 

 low as two or three feet, and then sud- 

 denly rising within a fortnight perhaps 

 to the height of 65 to 71 feet. 



The immediate bed of the Ohio varies 

 greatly in width. The two ranges of 

 limestone hills which border the river 

 throughout almost its entire length, in 

 places approach the channel, being with- 

 in three-quarters of a mile of each other, 



