3: PROLOGUE (Countercurrents)

At first glance, the Bosphorus is commonly mistaken as a large river when it is, in fact, a narrow sea channel forming part of a continental boundary.

On May 7th, 1873 Commander J. L. Wharton of H.M. Surveying-Ship Shearwater reported back to the British admiralty on the currents and undercurrents of the Dardanelles and Bosphorus:

Sir William Wharton by Harry M. Allen oil on canvas, circa 1907. Copyright (C) National Portrait Gallery

The general result of the undercurrent observations in the Dardanelles is, that an undercurrent exists whenever a surface one does, and invariably in an opposite direction. […]the whole of the water to the bottom is generally on the move in a contrary direction. At about 10 or 15 fathoms depth also the specific gravity of the water generally alters rapidly, approximating to the Mediterranean density below, aind to that of the Black Sea above. Observations on the Currents and Undercurrents of the and Bosphorus made by Commander J. L. Shearwater/ between the months of June and October 1872. From a Report of that Communi Officer to the Hydrographer of the Admiralty. Received May 7, Communicated by Admiral Richards C.B. V.P.R.S. Dardanelles Wharton of H.M. Surveying -Ship 1873.

The temperature also changes about this point, showing that it is not superfluous surface-water that is running back underneath, but that it is the Mediterranean supplying the place of the lighter Marmara water.

HMS Shearwater (1861) was one of a class of seven screw-sloops of wooden construction built for the Royal Navy. Rosario-class sloop Peterel

The western banks of the Bosphorus constitute the geographic starting point of the European continent, while the banks to the east are the geographic beginnings of the continent of Asia.

It's an internationally-significant waterway located in northwestern Turkey, and also a dialectical metaphor for concepts found in topological spaces, enumerating definitions of concepts such as discontinuity, relatedness and resemblance in BioCarta.