WHAT A DIFFERENCE a century has made in technology, design, engineering and science.

The advances made in that time make the feat of engineering that is the Panama Canal all the more incredible: one of the most important elements of its construction was completed this month 100 years ago exactly.

In May 1913, crews of hundreds and several steam shovels completed the digout of the Culebra Cut – which measured around 12km in length. The engineer which oversaw that section of the Panama Canal project since 1904, David du Bose Gaillard, died in December of 1913, before the whole project was completed.

This was the scene at the Gaillard Culebra Cut on 20 May 1913. You can see the American steam shovels, numbered 230 and 222, in the background. These helped dig out the section while dynamite is poured into the high towers on the upper level of the ditch. Some of the workers who had handlaid tracks are visible in the foreground:

This is how the project began – this photo shows a steam shovel excavating and loading dirt onto its cars in December 1904:

The-then US president Theodore Roosevelt is pictured here in his pale suit, ‘testing’ the controls of one of the steam shovel machines in November 1906. Roosevelt had championed the US involvement in the Panama Canal, which was to connect the Atlantic, via the Caribbean, to the Pacific. His visit here made him the first US president to travel abroad.

By January 1912, when this picture was taken, much of the Cut had been excavated and a crew of 150 men are seen here shifting tracks by hand for the steam shovels to complete their work.

The depth and scale of the Cut is visible from the remaining mountainous walls in the background:

Two years after the Gaillard Culebra Cut was completed, water filtered in and these slide dredges continued to refine the canal, seen here on 30 October 1915:

The Panama Canal officially opened in 1914, and a third lane of locks is currently being built there to allow larger container ships to pass through and reduce the backlog in ships waiting to cross.

This was how the Gaillard Cut or Corte Culebra looked in 2006:

All images from AP/Press Association Images archive

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