The policy of Philip was continued for about two centuries, although in the reign of his father many efforts had been made in the direction of a ship waterway across the Isthmus. In fact, ships crossed the Isthmus nearly four centuries before the completion of the canal. About 1521 Gil Gonzales was sent to the New World to seek out a strait through the Isthmus. He sailed up and down the Central American coast, entering this river and that, but failing of course to find a natural waterway. Not to be outdone, he decided to take his two caravels to pieces and to transport them across the Isthmus. He carried them on the backs of Indians and mules from the head of navigation on the Chagres River to the ancient city of Panama. There he rebuilt them and set out to sea, but they were lost in a storm. Still determined to make the most of his opportunities, Gonzales built others to take their places and with these made his way up the Pacific coast through the Gulf of Fonseca to Nicaragua, where he discovered Lake Nicaragua. A few years later another explorer made a trip across Lake Nicaragua and down the San Juan River to the Atlantic.
Cortez, the conquistador of Mexico, at one time was ordered to use every resource at his command in a search for the longed-for strait. He did not find it, but he did open up a line of communication across the Isthmus of Tehauntepec, following practically the same line as was afterwards followed by Eads with his proposed ship railway.
From those days to the time when the United States decided that the canal should be built at Panama and that it should be made a national undertaking, one route after another was proposed. In 1886, immediately after the French failure, the Senate requested the Secretary of the Navy to furnish all available information pertaining to the subject of a canal across the Isthmus, and Admiral Charles H. Davis reported that 19 canal and 7 railway projects had been proposed, the most northerly across the Isthmus of Tehauntepec and the most southerly across the Isthmus of Panama at the Gulf of Darien, 1,400 miles apart. Eight of these projects were located in Nicaragua.
In 1838 the Republic of New Granada, which then had territorial possession of the Isthmus of Panama, granted a concession to a French company to build a canal across the Isthmus. This company claimed to have found a pass through the mountains only 37 feet above sea level. In 1843 the French minister of foreign affairs instructed Napoleon Carella to investigate these claims. That engineer found no such pass and reported the claims to be worthless. He, in turn, advocated a canal along the route followed by the present Panama Canal, with a 3-mile tunnel through Culebra Mountain and with 18 locks on the Atlantic slope and 16 locks on the Pacific slope. He estimated the cost of such a canal at $25,000,000. The first formal surveys of the Panama route were made in 1827 by J. A. Lloyd. He recommended a combination rail and water route, with a canal on the Atlantic side and a railroad on the Pacific side.
The first serious proposition to build a Nicaragua Canal was made in 1779 when the King of England ordered an investigation into the feasibility of connecting the Nicaraguan lakes with the sea. A year later Capt. Horatio Nelson, destined to become the hero of Trafalgar, headed an expedition from Jamaica to possess the Nicaraguan lakes, which he considered to be the inland Gibraltar of Spanish America, commanding the only water pass between the oceans. His expedition was successful as far as overcoming Spanish opposition was concerned, but a deadlier enemy than the Don decimated his ranks. Of the 200 who set out with Nelson only 10 survived, and Nelson himself narrowly escaped with his life after a long illness.
In 1825 what now constitute the several countries of Central America were embraced in one federation—the Central American Republic. It asked the cooperation of the American people in the construction of a canal through Nicaragua. Henry Clay, then Secretary of State, favored the proposition, and, in 1826, the Federation entered into a contract with Aaron H. Palmer, of New York, for the construction of a canal through Nicaragua capable of accommodating the largest vessels afloat. Palmer was unable to command the necessary capital and the concession lapsed. A few years later an English corporation sent John Bailey to Nicaragua for the purpose of securing a canal concession. He failed to get the concession but was later employed by the Nicaraguan Government, which again had become independent, to determine the most feasible location for a canal across Nicaragua.
The United States Government became deeply interested in Isthmian Canal projects during the Forties of the last century. The extension of the national domain to the Pacific coast made the building of an Isthmian Canal a consideration of prime importance to the United States, and made it a dangerous policy to allow any other country to acquire a dominating hand over an Isthmian waterway. The result was that the American Government advised the British Government that it would not tolerate the control of any Isthmian Canal by any foreign power. This later brought about the Clayton-Bulwer treaty, which made neutral the proposed Nicaraguan Canal.
In 1849 Elijah Hise, representing the United States, negotiated a treaty with Nicaragua, by the terms of which that country gave to the United States, or its citizens, exclusive right to construct and operate roads, railways, canals, or any other medium of transportation across its territory between the two oceans. The consideration exacted by Nicaragua was that the United States should guarantee the independence of that country—a consideration that was then paramount because of the effort being made by Great Britain to gobble up the "Mosquito Coast" as far east as the San Juan River. The United States was not ready to give such a guarantee—although a half century later it did give it to the Republic of Panama—and the Hise treaty failed of ratification in the Senate.
A little later Cornelius Vanderbilt became interested in a canal and road across Nicaragua under an exclusive concession running for 85 years. Modifications of this concession permitted the Vanderbilt Company to exercise exclusive navigation rights on the lakes of Nicaragua. As a result the Accessory Transit Company established a transportation line from the Atlantic through the San Juan River and across Lake Nicaragua, thence by stage coach over a 13-mile stretch of road to San Juan del Sur on the Pacific.
In 1852 Col. Orville Childs made a report to President Fillmore upon the results of his surveys for a Nicaraguan Canal; and, if the United States, in 1902, had elected to build the Nicaraguan Canal, the route laid out by Childs would have been followed for all but a few miles of the entire distance. In 1858 a French citizen obtained from Nicaragua and Costa Rica a joint concession for a canal, which contained a provision that the French Government should have the right to keep two warships on Lake Nicaragua as long as the canal was in operation. The United States politely informed Nicaragua and Costa Rica that it would not permit any such agreement—that it would be a menace to the United States as long as the agreement was in force. Upon these representations the concession was canceled.