In 1835 Christopher Costigan rowed from Tiberias on the Sea of Galilee to Beth Shean, then traveled overland to the Dead Sea. 
     Thomas Howard Molyneux, a British lieutenant, rowed down the Jordan from Tiberias with three friends in 1847. After many clashes with unfriendly Bedouins they reached the Dead Sea. 
     William Francis Lynch, and American naval lieutenant, and thirteen men went down the Jordan in two boats, one of iron and one of copper, in 1848. They mapped the Jordan River and determined that the Dead Sea was 1300 feet below the level of the Mediterranean Sea. The map on the middle stamp is by Lynch. 
     During 1868 John MacGregor sailed his canoe, the Rob Roy, on Lake Hula, the Sea of Galilee and the Kishon River. He was taken prisoner by Bedouins on Lake Hula and later escaped. He mapped the lake and the Sea of Galilee. His canoe appears on the left-hand stamp on the sheet, and also on the lower margin.