Truths Universally Acknowledged

We hear them almost every day, but what do they actually mean? Here are the facts behind some common sayings:
At a snail's pace: The fastest land snail on record was called Archie. He won the 1995 World Snail Racing Championship in Congham, England, by covering 33 centimeters in two minutes and 20 seconds. That's 0.008kmph.
Just a moment: According to an old English time unit, a moment takes one and half minutes, but by rabbinical reckoning a moment is precisely 19/270 of an hour.
All the tea in China: The UN Food and Agriculture Organization estimates that all the tea in China amounts to 569,860 tonnes.
Since time immemorial: Time immemorial is usually defined as beyond the memory of any living person, or a time extending so far back as to be indefinite. However, for the purpose of English law, a status passes in 1275 decreed that time immemorial was any point prior to 1189-the year when Richard I began his reign.
Blood is thicker than water: In chemistry, water is given a specific gravity, or relative density, of 1.00, because it is used as the standard against which all other densities are measured. By comparison, blood has a specific gravity of 1.06-just slightly thicker than water.