The aircraft carriers of the Nimitz Class are the largest warships currently in service in the world. At around $4.5 billion each, these carriers are the most expensive ship on this list. The ten ships of this class help the United States flex its military muscle around the world.
Introduction to China Jaw Crusher. Jaw crushers machine are invented in 1858 and first widely applied in road paving and then in mines.
In 1850 Samuel S. Rembert and Jedediah Prescott of Memphis, Tennessee, received the first patent for a cotton harvester from the U.S. Patent Office, but it was almost a century later that a mechanical picker was commercially produced.