Search results
Results From The WOW.Com Content Network
While the pump-drill and the bow-drill were used in Western Civilization to bore smaller holes for a larger part of human history, the auger was used to drill larger holes starting sometime between Roman and Medieval ages. [9] The auger allowed for more torque for larger holes.
In a holdover from his duties hosting Mail Call on the History Channel, he frequently added humor in the form of light-hearted drill instructor haranguing aimed at the viewer. He also displayed an eagerness to try out the episode's relevant weapons against a wide range of targets, particularly watermelons ("they taste better after being shot ...
A French engineer, Alexandre Lavalley, who was also a Suez Canal contractor, used a similar machine to drill 1,669 m (5,476 ft) from Sangatte on the French side. [29] However, despite this success, the cross-Channel tunnel project was abandoned in 1883 after the British military raised fears that the tunnel might be used as an invasion route.
In a variation called the Egyptian bow drill, the cord is wound around the shaft multiple times, or is fixed to it by a knot or a hole. [citation needed] The strap drill is a simpler version, where the bow is absent and the cord is kept taut by pulling the ends with both hands, while moving them left and right at the same time. In the absence ...
Bow Drill: Bow drills were used in Mehrgarh between the 4th and 5th millennium BC. [13] This bow drill—used to drill holes into lapis lazuli and carnelian—was made of green jasper. [13] Similar drills were found in other parts of the Indus Valley Civilisation and Iran one millennium later. [13]
Later, the Holman Silver 303 Airleg was used all over the world for mine development. As well as the rock drills, the company also produced drill rigs and developed 'down the hole' drill primarily for quarrying. The company developed a hydraulic breaker, known as the Holbuster, but was ahead of its time and it was not a commercial success.
Thirty years ago, on April 19, 1993, after a 51-day siege by federal agents, the Branch Davidian complex in Waco erupted in flames, leading to the deaths of 76 people. Several projects timed ...
Freighter Fairpartner carrying the disassembled tunnel boring machine into the Port of Seattle in April 2013. Bertha was designed and manufactured by Hitachi Zosen Sakai Works of Osaka, Japan, and was the world's largest earth pressure balance tunnel boring machine, [14] at a cutterhead diameter of 57.5 feet (17.5 m) across.