Negrelli, the Italian-Austrian railroad pioneer, became interested in the idea in 1836. In 1846, Prosper Enfantin's Société d'Études du Canal de Suez invited a number of experts, among them Robert Stephenson, Negrelli and Paul-Adrien Bourdaloue to study the feasibility of the Suez Canal (with the assistance of Linant de Bellefonds). Bourdaloue's survey of the isthmus was the first generally accepted evidence that there was no practical difference in altitude between the two seas. Britain, however, feared that a canal open to everyone might interfere with its India trade and therefore preferred a connection by train from Alexandria via Cairo to Suez, which Stephenson eventually built. Construction by the Suez Canal Company Preparations (1854–1858) In 1854 and 1856, Ferdinand de Lesseps obtained a concession from Sa'id Pasha, the Khedive of Egypt and Sudan, to create a company to construct a canal open to ships of all nations. The company was to operate the canal for 99 years from its opening. De Lesseps had used his friendly relationship with Sa'id, which he had developed while he was a French diplomat in the 1830s. As stipulated in the concessions, de Lesseps convened the International Commission for the piercing of the isthmus of Suez (Commission Internationale pour le percement de l'isthme de Suez) consisting of 13 experts from seven countries, among them John Robinson McClean, later President of the Institution of Civil Engineers in London, and again Negrelli, to examine the plans developed by Linant de Bellefonds, and to advise on the feasibility of and the best route for the canal. After surveys and analyses in Egypt and discussions in Paris on various aspects of the canal, where many of Negrelli's ideas prevailed, the commission produced a unanimous report in December 1856 containing a detailed description of the canal complete with plans and profiles. The Suez Canal Company (Compagnie universelle du canal maritime de Suez) came into being on 15 December 1858. The British government had opposed the project from the outset to its completion. The British, who controlled both the Cape route and the Overland route to India and the Far East, favored the status quo, given that a canal might disrupt their commercial and maritime supremacy. Lord Palmerston, the project's most unwavering foe, confessed in the mid-1850s the real motive behind his opposition: that Britain's commercial and maritime relations would be overthrown by the opening of a new route, open to all