AN ASTONISHING ENGINEERING FEAT.

Otago Witness, Issue 2815, 26 February 1908, Page 87

AN ASTONISHING ENGINEERING FEAT.

(See Illustration elsewhere.)

a RAILWAY ACROSS THE SEA.

The Sphere of January 11 says : — A very flaring railway feat is now under way in the southernmost part of the tTniifti States. It will form an extension of the Florida. East Coaefc Railway. When completed it will catry passengers direct from New York to Key West without changing 1 . This being accomplished by virtually allowing the line to go to eea. at a point below Miami on the east coast of Florida. It then crosses 75 miles of open water by bridge or viaduct, traversing no fewer than 42 islands or iejs, before its destination is reached. — Crossing a Storm-swept Sea. —

The erection of the road in the open sea from one island to another called for the exercise of much engineering skill. In the first place the road is exposed to all the storms to which these tropical waters are s_ubje«ted. In many of the islands a wide swath will have to be cut, while on others the track "will have to be laboriously built up from below the_ sea-level. Much of the land which the' railway will cross consists of an almost impenetrable swamp. Although a tingle track the engineers estimate that the cost of construction will exceed £20,000 a mile, or about £3,000,000 for the 150 miles of construction from Miami j to Key West. — Constructed of Reinforced Concrete. — One of the most interesting parts of the •work to the lay mind is the precautions taken, to safeguard the exposed viaducts against the sea. The viaducts are being built of reinforced concrete resting either J on deep piling or solid rock. It has been found after careful examination that the maximum, height of waves throughout this region is 25ft, and the railway bed is being built at a level of more than 30ft Above high tide. — A Seven-mile Viaduct.— The longest of the viaducts over the ©pen sea-, that at Long Key, is- nearly seven miles. There are at present 2500 men employed on this viaduct -alone, working both day and night. This army of wckers is comfortably housed in a camp at the western end of Long Key. The will consist of 186 arches, and of these 70 are already completed. Some idea of the proportions, of this undertaking may be- gained from the statement that this viaduct will"- use up 286,000 barrels of cement, 177,000 cubic yards- of crushed rock, 106,000 cubic yards of. sand, 612,000 lineal feet of piling, 6700 tons of reinforcing rods, and 2,600,000 ft of -dressed lumber for arch (forms. -Ttesting on Coraline Limestone. — j cry possible- precaution, is. being > to anticipate the action of the wind d waves against this ocean-going railvav. The supporters of every one of the arches rest upoD 28 piles driven deep^into the coraline limestone which forms the bed of the sea. After the pile-drivers have passed to the next pier a cofferdam, is lowered from a catamaran into place around the 'piles. A long pipe is then tised to lay concrete to a depth of 3ft. As aoon. as this has hardened the water is pumped out and the pier forms are set fin. place around the piles,, which have ibeen out down, bo low-water level. A great barge containing- the cement-mixing machine is then towed into place, loaded with cement and crushed" rock. The steel reinforcing rods are put in place and the cement is poured in. It is allowed to etand for three weeks before the frame is Temoved. When completed the viaduct consists of a thick shell of cement, which is in turn filled in with earth and crushed rock to the track level. The water varies in depth from 13ft to 20ft. The tide under normal conditions flows at the rate of four miles an hour.

— Through Mangrove Swampte. — The 150 miles of constructive work between Miami and Key West presents practically every problem known to railway engineering. Shortly after leaving Miami a heavy, mangrove swamp was ettconntered, necessitating the- erection of epecial dredgers to clear away the mud and debris for a foundation. •

In carrying out the work on the viaduct a considerable flotilla of boats of various types are being used. There are now engaged on the 'work nine sternirheel boats, three tugs, 28 launches, and upwards of 50 pile-drivers, concrete mixing plants, derricks, pump barges, and dredgers-.

The longest stretch of track on any of the keys or islands, which are used by the engineers as stepping stones, is 16 miles. When the line is not passing over the open sea it traverses a high embankment which, commands a beautiful view over the surrounding land and sea. For long stretches the tracks are shaded by "waving forests of cocoanut palm, which -with the dazzling white of the coral makes an enchanting scene. At Key West a large harbour is being built. Here it is proposed to ferry the trains across to Havana, which is only 90 miles distant. This will mean that by this unique railway one will shortly be able to go all ihe war from New York to Havana by train without changing.

— It's a. pity that the woman who knows How to manage a husband never bad one_ and never will have.

Sore fend swollen: joints, sharps ehootinjf pains, - tortured muscles, no rest, no sleep. When, you feel like this. 1 it means that you bave rheumatism. It is a stubborn, disease to fi«bt, but Chamberlain's Fain Balm has conquered thousands of times, 'xn.3. will do so aff&in. Don't eiperinjent with other medicines, 'bat- fret Chamberlain's Pi?n !Balm- «t onoe and follow ■ tpe directions : the first application will «v«" you relief and by continual use it will effect a cure For sale everywhere.