Wegener also noted that the continents move up and down to maintain equilibrium in a process called isostasy. As an example he cited the sinking of Northern Hemisphere lands under the weight of continental ice sheets in the last ice age, and their rise since the ice melted some 10,000 years ago.
Drill that is fitted with a Pipe provides effective connection to the rig surface equipment or application with the bit and the bottom hole assembly for the purpose of pumping the Drill fluid to the bit.
Many drill procedures used by the United States Army today were developed during the Revolutionary. War. The purpose of the drill then was to instill discipline in American soldiers. As these soldiers. mastered the art of the drill, they began to work as a team and to develop a sense of pride in themselves. and in their unit. In todayâs Army, the same objectivesâteamwork, confidence, pride, alertness, attention to detail, esprit de corps, and disciplineâare accomplished by drill.