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Rough and gray as rock, I'm pl...

Rough and gray as rock, I'm plain as plain can be. But hidden deep inside there's great beauty in me. What am I?

Correct answers: 141

The first user who solved this task is Sanja Šabović.

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What Gear Were You In?

Policeman to Blonde: What gear were you in at the moment of the impact?

Blonde: Gucci sweats and Reeboks.

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Guncotton patent

In 1846, Christian Frederick Schönbein of Basle, Switzerland, was issued a U.S. Patent for guncotton titled “Improvement in Preparation of Cotton-Wool and Other Substances as Substitutes for Gunpowder”(No. 4874). The process uses a mixture of concentrated acids to convert the cellulose present in well-cleaned cotton-wool, C6H10O5 into cellulose nitrate C6H8(NO2)2O5 (nitrocellulose). In 1891, James Dewar and Frederick Abel incorporated nitrocellulose in a mixture that could be handled more safely. Until WW II, this invention replaced gunpower on the battlefield, where it had been used for five centuries. It was also useful for blasting because it generates about six times the gas of an equal volume of gunpowder and produces less smoke and heat.

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