Bridge over the Big Black River. 41 DESTRUCTION OF THE RAILROAD BRIDGE OVER THE BIG BLACK RIVER _-13~ WM. E. MORRIS, Civil Engineer. About the year 1839 there was erected upon the Railroad between Vicksburg and Jackson, Mississippi, a high bridge across the Big Black River.
It was destroyed during the recent war and rebuilt in 1865 and '66. There were three spans, respectively 105, 140 and 165 feet in length, supported u:on three high piers and one small a,butment pier.
The two middle piers stood in the bed of the river, the eastern one upon a low flat of land not many feet above surface of low water, while the western one, serving as an abutment, was built upon a steep clay bank that formed the western shore of the river.
The abutment was built of brick, about 10 feet in height, while the rn! 'Idle piers had a height of about 80 feet, the lower L'5 feet constructed of granite and the upper 55 feet of brick masonry. Upon the eastern side the approach to the bridge was upon a high trestle work.
The bridge was rebuilt upon the " Fink Plan," with wooden chords, wrought iron suspension rods and cast iron bearing columns, with the road-way carried upon the chords.
This was the most important and expensive structure upon the road, and its stability and permanence was justly considered by the officers of the company, of great moment.
After the annual meeting of the company, on the first Monday of May, 1874, the president, several of the directors, the superintendent of the road and myself, visited the bridge and fornd it in good condition, though the water of the river was quite high, some 25 feet above low water.
Ten days afterwards, the west bank of the river, both below the west abutment and in its rear, began to crack and slide slowly into the river.
This continued until the abutment slid out of its position obliquely down the bank, throwing upon the sloping bank below, the western span of the bridge.
Two days afterwards the western pier was noticed to be moving bodily eastward, latterally.
This it continued to do for several days,