brian@advsys.UUCP (Brian Rippon) (01/17/90)
In article <50949@bbn.COM> news@bbn.COM (News system owner ID) writes: >The "conventional American" point IS kind-of metricized: The 1886 >standard from the United States Type Founders' Association was based on >the observation that the American-pica had an almost-relationship to >the cm: > > 83 picas ~= 35 cm > >and so they standardized on exactly "83 picas = 35 cm". Well, I'm confused. How big was a centimetre in the US in those days? Since SI, there are 2.54 cm/inch, so you would get 72.2811428571... points/inch. Now to quote Stephenson Blake & Co. Ltd (1915), "In 1886 the United States Type Founder's Association adopted the present American Point Standard, taking as their unit a pica measuring .166044 inch divided into twelve equal parts which were called points. The American point (sic) therefore measures .013837 inch. The above figures are given on the authority of the American Type Founders' Co." If that was right, you get 72.270000722700007227... points/inch. That given, it's all an approximation, and 72 sounds as good a number as any other. Fournier and Adobe chose well. Brian.
cosell@bbn.com (Bernie Cosell) (01/19/90)
brian@advsys.UUCP (Brian Rippon) writes: }In article <50949@bbn.COM> news@bbn.COM (News system owner ID) writes: }>The "conventional American" point IS kind-of metricized: The 1886 }>standard from the United States Type Founders' Association was based on }>the observation that the American-pica had an almost-relationship to }>the cm: }> }> 83 picas ~= 35 cm }> }>and so they standardized on exactly "83 picas = 35 cm". }Well, I'm confused. How big was a centimetre in the US in those days? }Since SI, there are 2.54 cm/inch, so you would get 72.2811428571... points/inch. I did some poking, and I think that you are correct: the "length of the inch" probably changed. The French instituted the metric system in 1799. The point was "standardized" in 1886, and in fact probably *did* work out to be 72.28 points/inch. In 1893 the United States officially reconciled its units with the Metric units. I could easily believe that the length of the foot [or the length of the meter... depends on your point of view...:-)] changed by one part in ten-thousand at that point. In particular, notice that the "exact" value for the centimeter is by definition 2.54 cm/inch. That looks suspiciously like "three significant digits", and so would be an approximation which would introduce an error at the fourth digit... and look at what position we seem to have picked up some error at.... }That given, it's all an approximation, and 72 sounds as good a number }as any other. Fournier and Adobe chose well. I agree. Time to let this thread die.... /Bernie\