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Products of a Misspent Youth: Basic Multiplication 49
Zerah Colburn: Entertaining Calculations
One of the first lightning calculators to capitalize on his talent
was Zerah Colburn (1804–1839), an American farmer’s son
from Vermont who learned the multiplication tables to 100 before he
could even read or write. By the age of six, young Zerah’s father took
him on the road, where his performances generated enough capital to
send him to school in Paris and London. By age eight he was internationally
famous, performing lightning calculations in England, and was
described in the Annual Register as “the most singular phenomenon in
the history of the human mind that perhaps ever existed.” No less
than Michael Faraday and Samuel Morse admired him.
No matter where he went, Colburn met all challengers with speed
and precision. He tells us in his autobiography of one set of problems
he was given in New Hampshire in June 1811: “How many days and
hours since the Christian Era commenced, 1811 years ago? Answered
in twenty seconds: 661,015 days, 15,864,360 hours. How many seconds
in eleven years? Answered in four seconds; 346,896,000.” Colburn
used the same techniques described in this book to compute
entirely in his head problems given to him. For example, he would factor
large numbers into smaller numbers and then multiply: Colburn
once multiplied 21,734 543 by factoring 543 into 181 3. He then
multiplied 21,734 181 to arrive at 3,933,854, and finally multiplied
that figure by 3, for a total of 11,801,562.
As is often the case with lightning calculators, interest in Colburn’s
amazing skills diminished with time, and by the age of twenty he had
returned to America and become a Methodist preacher. He died at a
youthful thirty-five. In summarizing his skills as a lightning calculator,
and the advantage such an ability affords, Colburn reflected,“True, the
method...requires a much larger number of figures than the common
Rule, but it will be remembered that pen, ink and paper cost
Zerah very little when engaged in a sum.”