    Ð°Ð½ Obstetrician is a physician who has successfully completed specialized education and training in the management of pregnancy, labor, and the puerperium (the t â¦ ime-period directly following childbirth).n Obstetrician specializes in the care and treatment of pregnant women during their pregnancy, labor, delivery and the postpartum period.
Animal skins were used as sails for the earliest boats and rafts. The Egyptians and other ancient people wove reeds together in mats to make sails, but the Egyptians were also the first to make cloth sails as early as 3300 B.C. Great sailors of the Mediterranean region like the Phoenicians sailed under cloth sails.
Square sails had a crest-like bottom called a roach. The square sail was good for sailing if the wind was blowing behind or to the side of the sail, but not good for sailing into the wind. (b) Lateen sails were used first on Arab ships and then Mediterranean vessels. They started in a right triangle shape with the top corner attached to the mast but soon the lower point of the sail was cut off the the sail attached to the mast at the bottom as well, with a pole along the bottom edge to keep it straight.