Conceive a sphere constructed with the earth at it center, and imagine it surface to pass through Sirius, which is 8.8 light years distant from the earth... Then imagine this enormous sphere to be so packed with microbes that in every cubic millimetre millions and millions of these diminutive animalcula are present. Now conceive these microbes to be unpacked and so distributed singly along a straight line that every two microbes are as far distant from each other as Sirius is from us... Conceive the long line thus fixed by all the microbes at the diameter of a circle, and imagine its circumference to be calculated by multiplying it diameter by Pi to 100 decimal places. Then, in the case of a circle of this enormous magnitude even, the circumference so calculated would not vary from the real circumference by a millionth part of a millimeter.

This example will suffice to show that the calculation of Pi to 100 or 500 decimal places is wholly useless.

-- Hermann Schubart, a mathematics professor from Hamburg in 1889