Where is isthmus of tehuantepec mexico on the map

It represents the shortest distance between the Gulf of Mexico and the Pacific Ocean. At its narrowest point, the isthmus is approximately km mi across. The Sierra Madre breaks down at this point into a broad, plateau-like ridge. The northern side is swampy and densely covered with tropical forest; the Pacific slopes on the south are drier.

The population is composed almost wholly of indigenous Zapotec peoples. The women are the traders and do little menial work. Known as "Tehuanas," these women are known throughout Mexico for their colorful dresses, assertive personalities, and relatively equal relations with men, leading some to characterize them as "matriarchal". The predominant climates in the region are tropical savanna primarily in the south and tropical monsoon primarily in the north.

There are also small central areas with a temperate climate due to elevation. The narrowness of the isthmus, and the gap in the Sierra Madre, allow the trade winds from the Gulf of Mexico to blow through to the Pacific. Normally, these winds are not particularly strong. Periodically however, a surge of denser air originating from the North American continent will send strong winds through the Chivela Pass and out over the Gulf of Tehuantepec on the Pacific coast. This wind is known as the Tehuano.

Prior to the opening of the Panama Canal , the isthmus was a major shipping route, known simply as the Tehuantepec Route. However, it was rejected as an interoceanic canal site because construction of the canal would have been too costly. After the Civil War, he'd built the St. Louis Bridge across the Mississippi, with the longest steel arches ever made.

During the War he'd built many of the Union's big ironclad gunboats. He was to America what de Lesseps was to France. He knew how hard it would be to build a system of locks across Panama. Instead, he proposed a rail system for moving ships overland, across the Isthmus of Tehuantepec. He planned to slide a foot flat bed under ships in a foot dry dock.

Three double locomotives abreast would pull the ships onto dry land and across Mexico on three parallel sets of railroad track. Adjustable rams on the flat bed would form a cradle, unique to each ship's hull. Eades went to Congress with his plan.

In he learned that the Senate had approved his idea. He died a few months later, without ever knowing that the House of Representatives subsequently blocked it. Eads had argued that the cost of his plan would be only half the cost of either building or maintaining a canal; most ocean trips would be two thousand miles shorter; and on rail, ships would cross land twice as rapidly as in a canal. America and France ultimately paid a terrible price for the canal, in both money and human life.

The history of engineering is filled with tantalizing what-ifs. But few are so filled with possibility as the image of Eads' ships moving with stately grace, by rail, across Mexico. I'm John Lienhard, at the University of Houston, where we're interested in the way inventive minds work.

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