
hitherto-impossible task
The World Of Wonders A Record …[1]
about 5.5 times heavier than a ball of water of the same size and form
The World Of Wonders A Record …[2]

five or six times greater than that of water
Sir Isaac Newton[3]
5,852,000,000,000,000,000,000 tons, of 2,240 lbs. to the ton
Sir John Herschel[4]
What mere assertion... will make any one believe...
Sir John Herschel[5]
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