There are some scientific propositions that at first seem to be utterly pointless, and trying to find the weight of the earth seems to be one of them. Until you realise that weight affects gravity, so is incredibly important in astronomy, which was an incredibly popular subject in the 18th century, as its role in navigation was vital to commerce. William Herschell was one of the most famous astronomers of his day, but less known was Francis Bailey, who was the first man to weigh the earth.
This is from ‘And So To Bath’
“Sir William Herschell knew him well, he was a frequent caller at Slough, and Sir John Herschell wrote his life. He was born at Newbury in 1774 where his father, who came from Thatcham, was in business as a banker. Young Baily was so learned and ‘ingeniose’ as they would say, that he coon got the nickname of the Philosopher of Newbury. But his father was firm, and into the City went young Francis. He broke the shackles at 22 and in 1775 off he went to the United States, whence, of the future capital of Washington he wrote home: “Game is plentiful in these parts, and what may seem remarkable, I saw some boys who were out a-shooting actually kill several brace of partridges in what will be one of the most public streets of the city.” He also added that building lots, uncleared, were selling from 3 pence to 1 shilling per square foot.
Sailing home, he was taken prisoner by the French.[ Back in England]. He now went into business as a stock-broker where he made a modest fortune, but his heart was in astronomy, so he retired at 50 and in a few years had made a great name in astronomical circles. He reformed the Nautical Almanac, revised the catalogue of the stars, corrected the calculations of the pendulum, so that our clocks have become more accurate, revised and corrected the British standard of length, so that ladies now buy a correct yard of material, and gentlemen can walk an exact mile, and then, as a make-weight as it were – he weighed the Earth!
But that was not all. He immortalised his name by giving he astronomical world Baily’s Beads. This phenomenon.. is seen during a total eclipse of the sun. Just before the disc of the moon completely covers the sun, the smooth crescent of overlapping sunlight is broken in several places, giving an appearance somewhat like a string of beads. This is due to the irregular outline formed by the mountains on the rim of the moon’s disc. Baily first saw this phenomenon on May 15th, 1836, during an annular eclipse of the sun. His discovery started a series of eclipse expeditions, including the totality of July 8th, 1842, which he observed at Pavia. He died in 1844, was buried in the family vault at Thatcham. ”
BTW the earth weighs 6 with 25 zeroes kilograms or 1.3 with 26 pounds .