Forth
a river of Scotland, rising on the E. side of Ben Lomond, in Stirlingshire. After a sinuous course E. past Aberfoyle, Stirling, and Alloa, it unites with an arm of the sea called the Firth of Forth. Its chief affluents are the Teith, Allan, and Devon. The Firth at its mouth is 35 or 40 miles wide, from Fife Ness on the N., to St. Abb's Head on the S. shore, both washed by the German Ocean. It contains several islands, of which the chief are Inchgarvie, Inchcolm, Inchkeith, the Bass, and the Isle of May; the largest of these is but a few miles in circuit. Lighthouses are erected on Inchkeith and on the Isle of May. The Forth possesses many good harbors, and St. Margaret's Hope, above FORTIFICATION Queen's Ferry, is one of the safest roadsteads in the island. Length of river, including its "links," 180 miles.