BOSPORUS, or BOSPHORTJS (Gk. B60- fropos, Bosporos, literally ox-ford, from f3oi3s. boas, ox, cow + fr6pos, poros, ford. crossing. Called also the Strait of Constantinople). The nar row channel which connects the Black Sea with the Sea of Slarmora and separates the two con tinents of Europe and Asia (Slap: Turkey in Europe, G 4). It has a length of about IS miles, and in width varies from about 1800 feet to about two miles, with a depth of over 100 feet.
The surface currents are from the Black Sea to the Sea of Marmon', while underneath and along the shore the direction is opposite, which fact accounts for the undiminished salinity of the Black Sea, in spite of the great quantities of fresh water which it receives through its atiluents. The swift currents and the occasional fogs which envelop the northern entrance make the channel very dangerous for navigation, and a number of lighthouses have been erected to insure greater safety. The shores are for the most part elevated, and in the vicinity of Constantinople are lined with palaces, picturesque villages, vineyards. and numerous ancient ruins. The
name Bosporus, which means an ox-ford or a cow-ford, is supposed to have been derived from the legend according to which the strait was crossed by to after she was transformed into a cow. Other authorities attribute the name to the narrowness of the channel, which makes it possible for an ox to cross it. The channel was also known at one time as the Thracian Bos porus. At the middle of this strait, where it is about 2800 feet in breadth, Darius made his bridge of boats when he marched against the Seythians. The Bosporus has long been under Turkish control. Repeated European confer epees. including that of Berlin. in 1S7S, have confirmed the stipulation of the treaty made in 1841, providing that no ship of war belonging to any nation but Turkey shall pass through the Bosporus without the consent of the Ottoman authorities.