    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.
The plow evolved from the all-wood designs of antiquity, to the use of iron parts. In 1720, the first English patent for a wooden moldboard sheathed with iron was issued to Joseph Foljambe. From that the evolution to plows made with cast iron moldboards and shares occurred in Scotland in 1785 by James Small. These cast iron plows were then imported to the U.S. Charles Newbold, born in Chesterfield, NJ (1780), spent his teenage years investigating the use of cast iron to improve on the heavy iron-clad wooden plow then available. He was issued the first US patent for a plow on 26 Jun 1797.