nPostednon September 4, 2013
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Picturena guy at his work table, tinkering with stuff, inventing stuff—allnwhile wearing a coonskin hat!
Picturena guy at his work table, tinkering with stuff, inventing stuff—allnwhile wearing a coonskin hat!n
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nThat’snour birthday boy, Swedish philosopher and inventor Martin Wiberg. Heninvented lots of things. Some stand-outs were his pulse jet enginen(remember, this was before successful air flight) and a creamnseparator. But Wiberg is most famous for his logarithmic tables machine.
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nWibergnhad heard about the work of Per Georg Scheutz and Charles Babbage,nwho had created large calculating machines. Fascinatingnstuff – can you imagine a machine capable of adding and multiplyingnand subtracting and dividing numbers? Of course you can—it’s soncommon today that many adults worry that children won’t figure outnhow to do arithmetic without machines! But back in the 1800s, whennWiberg lived, it was revolutionary! Some didn’t think it could be done. Still, inventors tinkerednwith machinery and figured out how to build mechanical calculators.
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Scheutz’sncalculator was about the size of a piano. It could create logarithmicntables—but it couldn’t produce complete tables. Wiberg went to worknon an entirely new design, and he created a much smallerncalculator—about the size of a sewing machine—that could produce complete logarithmic tables!
Scheutz’sncalculator was about the size of a piano. It could create logarithmicntables—but it couldn’t produce complete tables. Wiberg went to worknon an entirely new design, and he created a much smallerncalculator—about the size of a sewing machine—that could produce complete logarithmic tables!n
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nWhat’sna logarithmic table?
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It is NOT a table built from logs!
It is NOT a table built from logs!n
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nIt’s a chart that shows a certain mathematical function.
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nThenlogarithm of a number is the number of times that a base number mustnbe multiplied by itself to produce that number. n
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nIsnthat confusing? I will give you a simple example. Logarithms withnbase 10 are called “the common logarithm.” So the log of 10,000 (to base 10) is 4, because you have to multiply 10 by itself four timesnto reach that number (10 x 10 x 10 x 10 = 10,000). And the log of 100nto base 10 is 2, and the log of 1,000,000 is 6, and thenlog of 1,000 is 3.
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nWenuse the words “power of” and “exponent” when we talk about multiplying annumber times itself. To translate our examples into this language:
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n100n = 10 x 10 =
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n10 to the second power = 10^(2) n
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nSo….n2 = log 10 (100)
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n1,000n = 10 x 10 x 10 =
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n10 to the third power = 10^(3) n
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nSo….n3 = log 10 (1,000)
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n10,000n = 10 x 10 x 10 x 10 =
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n10 to the fourth power = 10^(4) n
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nSo….n4 = log 10 (10,000)
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n1,000,000n = 10 x 10 x 10 x 10 x 10 x 10 =
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n10 to the sixth power = n10^(6) n
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nSo….n6 = log 10 (1,000,000)
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nYounmay not realize how often logarithms are used it everyday life, butnthey are needed to compute interest on loans or investments, or tonanalyze how fast things are traveling. We use logarithmic scales whennwe talk about how powerful an earthquake is, or how loud a sound is.nOur gas gauges are using logarithms as they tell us to put more fuelnin our cars. n
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nToday we are lucky, because modern calculators and computers easilyncompute things like logarithms…but it is because of computernpioneers like Babbage, Scheutz, and Wiberg that we even havencomputers! So if you use a computer today (and, yes, I’m includingnyour game system, your phone, and your car!), take a moment to saynthank you to Mr. Wiberg!
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nAndnmaybe even give him a tip of your coonskin hat!
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nTonlearn more about logarithms, check out Math Is Fun or Steve Kelly’s TED Ed video.
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nAlsonon this date:
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Rosh Hashanah
Rosh Hashanah n
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nNewspaper Carrier Day
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nCivilnServants’ Day in Venezuela
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nBirthday of Los Angeles
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nPlannAhead!
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nChecknout my Pinterest pages on Septembernholidays, Septembernbirthdays, and historicalnanniversaries in September.
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nAndnhere are my Pinterest pages on Octobernholidays, Octobernbirthdays, and historicalnanniversaries in October.
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