Oh dear. Please go metric US. Please. We will help you.
Jim On 27 June 2013 11:33, Hal Murray <hmur...@megapathdsl.net> wrote: > > j...@quikus.com said: > > There WERE (past tense) a number of definitions of the inch, ranging from > > lines on bars of PtIr to a string of grain kernels. > > > Now there IS (present tense) one, defined as 2.54 cm. > > Except... > > http://en.wikipedia.org/wiki/Foot_%28unit%29#International_foot > > When the international foot was defined in 1959, a great deal of survey > data > was already available based on the former definitions, especially in the > United States and in India. The small difference between the survey and the > international foot would not be detectable on a survey of a small parcel, > but > becomes significant for mapping, or when the state plane coordinate system > is > used in the US, because the origin of the system may be hundreds of > thousands > of feet (hundreds of miles) from the point of interest. Hence the previous > definitions continued to be used for surveying in the United States and > India > for many years, and are denoted survey feet to distinguish them from the > international foot. The United Kingdom was unaffected by this problem, as > the > retriangulation of Great Britain (1936-62) had been done in meters. > > The United States survey foot is defined as exactly 1200/3937 meter, > approximately 0.3048006096 m.[ > > -- > These are my opinions. I hate spam. > > > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.