Arkansas true Democrat., 1858-11-03

tres that the conditions for artificial reservo;rs abound--n ridges. with narrow gorges or TO- vines, ln front of branching valleys. The hiob. CT the barriers thrown across these defiles. fbe greater the volume of waters contained beh;nd them, the safer becomes the river bed below. but the more carefully aud costly must thev he constructed, for the more terrible will he t6e;r accidental rupture. When the sixty-foot dam on the Lehigh, in the ravne of the Pokono mountain, broke, its solid wave swept every bridge and dam below it, with canal banks locks, mills and villages, away in indiscriminate rum to Its mouth. And when, fifty years ago. the high mll-dam on the Codorus broke away similar wave followed the windings of the stream Tor dozen miles; and although there was tune tor the millers son to saddle his horse and galop across to York to warn the yillaoe folks, yet, while they talked over the event and laughed at the danger, 1t approached with a oreastlng like the Bore of the Gauges, and swept off half their property.
 The rewooding of naked soils is not so inn portant in the New as in the Old World vet. nor will 1t ever be on the eastern side of the continent as 1t is fast becoming to the inhabi- tants of the great valley. But if every year a single atfiuent Of destructive river basin were rewooded, the change would soon be apparent. especially since trees but three years old have a marked efficacy. Here it is not national wealth or science so much as national persever- ance that is wanted, and that we know to be a rarest virtue
 The mbankment of leveeing of rivers has not yet become a science, but Is in its rude state or local chance construction. When the fall of river exceeds eight feet to the mile its le wees should De continuous and double; that is, one line of bank outside or behind the other on each side, for the strength of the flood and the weakness of the barrier increase together when single levee is used, which is an ira tonal arrangement. And yet this is the very arrangement hitherto universally adopted.- hiS Is an important point to which we call the attention ot all western men and civil en. glneers. The first bank should be low. to meet the ordinary stage of water. Let every fresbet override this quietly, as it would at first. and spend It's volume, and of course its strength. over certain space behind, and then find a SC. cond and consequently much stronger barrier. over which 1t could never break. And then where ever this intermediate and overhowed country Is cultivated, instead of attemptipr to protect It agalnst overflow, vain attempt. and al the same tune robbng of its natural right to the enrlchlng deposit of the overflow. let a su- Ter way be taken. Let strong transver.e dykes be projected across it, at proper intervals. not to keep out the water, but to stop the current and protect the soil while it is thus submerged
 M Dausse shows also the best form of hank to be the normal gently sloping talus of a na- tural rlver shore deposit, and not the abrupt slope oi artificial masonry. Itis, however, not by any means always that this form can he oh. tanned, as for instance, where a river sweeps round sharp bend; but even there some ap proxmalon can be made to it. The disasters oi the present year, and of late years, in Loui sana, were distinctly prophesied by an able United States engineer, while superintendinq the construction of the public works in that city some years ago, at the time when so many bends ot the Mississippi were cut through to shorten Its channel for the convenience of com. merce and, as 1t was alleged, to add security to the delta against inundations, by straightening the river and allowing 1t to SCOUT out its bed bv increasing its fall. This gentleman was wise enough to see and bold enough to say that these awkard and tedious horseshoe bends were so much natural reservoir to take and hold the surplus of the annual flow, and that to cut them oH was not only an unnatural, but suicidal policy the consequences of which have at length been recognized and lamented by many who secuted his theory as silly dream.
 The history of Holland and of Lombardv is a history of single dykes and terrible disasters. he delta of the Mississippi is no more subject to the runous consequences of mans interfer- ence with natures arrangements than the del- tas of the Hoang- ho or of the Danube.n