p.300 It has been remarked that from the year 1706 to the year 1808 ,the depth of this sea has diminished 3 feet; and from this latter date to the year 1833, it has again diminished 3 feet, so that it has lost 6 feet of depth in 127 years. This diminution in depth is caused by the accumulation of sand and mud from the Don, and in some measure likewise by the large quantities of ballast that are yearly thrown into the sea, by vessels loading in the roadstead of Taganrok. The sand bans have increased in extent, and new ones have been formed; which render the navigation of this sea daily more difficult and perilous.