Most dangerous in its possibilities was the controversy with Great Britain over the boundary between British Guiana and Venezuela. British Guiana lies on the northern coast of South America, next to Venezuela and extends inland, with its western boundary roughly parallel to the valley of the Orinoco River. A long-standing disagreement had existed about the exact position of the line between the two countries--a disagreement which harked back to the claims of the Dutch, who had acquired Guiana in 1613 and had turned it over to the British in 1814. In 1840 England commissioned a surveyor named Schomburgk to fix the boundary but his decision was objected to by the Venezuelans who claimed that he included a great area that rightfully belonged to them. Gradually the British claims included more and more of the territory claimed by Venezuela, and the discovery of gold in the disputed region not only drew attention to the necessity of a settlement of the boundary but also attracted prospectors who began to occupy the land. In 1876 Venezuela began negotiations for some means of deciding the dispute and came to the conclusion that arbitration was her only recourse. On the refusal of Great Britain to heed her protests, the Venezuelan government suspended diplomatic relations in 1887, although the United States attempted to prevent a rupture by suggesting the submission of the difference to an arbitral tribunal. This offer was not accepted by Great Britain, and repeated exertions on the part of both Venezuela and the United States at later times failed to produce better results. When Cleveland returned to the presidency in 1893 he again became interested in the Venezuelan matter and Secretary of State Gresham urged the attention of the British government to the desirability of arbitration.