[USMA:30429] Re: Fw: your "Metric Meddlers" column in the Telegraph

[David King]

The inch is precisely defined as 25.4 mm, however, this can never be more precise than metric. As MightyChimp wrote, FFUs are today defined more by their metric equivalents. For centuries the imperial measurements have changed over time, between places and sometimes the names changed, where is precision in that? It is so unprecise that we need the metric system, as that has a precision that no other system ever had. The length of a man's foot (e.g. a king or emperor) is not precise for creating a unit length, after all, his feet may shrink with age, and when he's dead then whose foot does society then use as the measuring unit? David MightyChimp wrote:   Which "old fashioned" units are more precise then metric units?  This statement in itself is in error.  A unit can not be precise, only the definition of it can be.  SI units are all precisely defined by a physical referance.  FFU units are defined from SI and their precision depends on how accurate the conversion factor is.    Also the precision of the measuring device plays a role in how precise a measurement is.