What is associated with: at the pantheon in paris in 1851 he demonstrated the earths rotation using his famous pendulum?

Based on the clue 'at the outbreak of hostilities of the civil war he...', what is the answer? Based on the clue 'at the outbreak of the civil war he hired a staff ...', what is the answer? Based on the clue 'at the outbreak of the war he was named hitlers of...', what is the answer? Based on the clue 'at the outbreak of wwii general joseph stilwell be...', what is the answer? What is associated with: at the paris observatory in the 1670s the speed of this was calculated as 140000 miles per sec… Based on the clue 'at the park the full bucket type of this is for 2 ...', what is the answer? Based on the clue 'at the party for the prodigal son there was music ...', what is the answer? Based on the clue 'at the party i impressed a beautiful woman by fibb...', what is the answer?