Marmora
2 of the 7 encyclopedias on this shelf carry an entry for Marmora. Both are reproduced below, so you can see where they agree and where they differ.
Collier's New Encyclopedia (1921)
or MARMARA (mär'-) ( ancient Propontis) , a small sea between European and Asiatic Turkey, communicating with the Ægean Strait of the Dardanelles (anciently Helan Sea by the lespont ), and with the Black Sea by the Strait of Constantinople ( anciently Bosporus). It is of an oval form, and about 135 miles in length, by 45 in breadth, but has, besides , a large gulf, the Gulf of Isnikmid, or Ismid, which extends about 30 miles E. into Asia. Its depth is great. There is a current from the Bosporus through it and the Hellespont MARMOSET the middle and gray at tip. The head is small, the nose flat, the face black, with a long tuft of white hair sticking out from each side. The tail is long and bushy, marked with alternate rings of ash-color and black. H. humeralifer is the cloaked marmoset. The fore part of the body is white; the hands gray; the rump and underside deadish-tawny; tail ouistiti. banded with gray and also individual of the genus Arctomys, but
Aiton's Encyclopedia (1910)
a sea between Asia and Europe. The waters of the Black Sea reach it through the Bosporus. It discharges its waters into the Aegean through the Dardanelles. It bears much the same relation to the Black Sea and the Mediterranean that is sustained by Lake St. Clair to Lakes Huron and Erie. Length, 170 miles; greatest width, 50 miles. An island of the same name lies in the sea. It is about eleven miles long. See Hellespont