| 1. | You must use special percussion drill bits for this operation.
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| 2. | In 1849, Couch's assistant, Joseph W . Fowle, filed a patent caveat for a percussion drill of his own design.
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| 3. | The commissioned stonemason used percussion drills to get the iron pins out that held the pieces of the granite together.
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| 4. | The percussion drill is designed to go down to and collect cemented ice samples for an onboard miniaturised laboratory called ProSPA.
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| 5. | The first " percussion drill " was made in 1848 and patented in 1849 by Jonathan J . Couch of Philadelphia, Pennsylvania.
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