International Commission for the piercing of the isthmus of Suez

The surveys made by Paul-Adrien Bourdaloue in 1847 during an expedition of the Société d'Études du Canal de Suez were the first generally accepted evidence that there was in fact no such difference.

During the same expedition, Alois Negrelli, the Austrian railroad pioneer, explored the bay of Pelusium at the northern end of the anticipated canal.

Thus, in his second, more detailed firman of 19 May 1855, the viceroy ordered to further elaborate the initial draft and to submit it to an international commission of experts for discussion and evaluation.

Negrelli provided the soundings and the alignment of the canal which he had drawn up during his visit of 1847 and which corresponded to a large extent to the draft made by Linant and Mougel.

Subsequently, they went north to Lake Timsah and the Wadi Tumilat to undertake boreholes and subsoil investigations and to examine the line of a canal across the Nile delta to Alexandria proposed by Jacques-Marie Le Père and by Paulin Talabot.

In his 1864 presidential address to the Institution of Civil Engineers, John Robinson McClean detailed his view of the two contrasting systems proposed for the construction of the Canal.

[4] British proposals continued to insist that there was a difference in water level between the Red and Mediterranean Seas of some 7 metres, despite the fact that survey work as early as 1847 had shown this not to be the case.

[16] Key resolutions included the decision against continuous embankments in areas where the canal traversed the Bitter Lakes, deeming them unnecessary.

It specified the canal's dimensions, recommending a depth of 8 metres (approximately 26.4 feet), with a width sufficient to accommodate two passing vessels and a third stationary line.

This decision, influenced by the recommendations of Mr. Larousse, a French Navy hydrographer, was based on finding an adequate depth of 8 metres closer to Port Said than the initially proposed eastern entrance.

[16] At Port Said, the jetties' design, including their length and construction method, was later adopted based on the advice of Mr. Pascal, Inspector-General of Roads and Bridges.

Geographische Gesellschaft (Imperial Royal Geographic Society) in Vienna about the intended canal and presented them with a copy of the commission's final report.