The "size" of the SI meter has its basis in the metric system and it was officially accepted in 1799. We know its size doesn't match its intended 1/10,000,000th division from the equator to the pole, thus it is somewhat arbitrary. Even though the SI meter is defined differently its "size" is the same as that approved in 1799. Those the created the meter were not aware that its size would be used to establish the velocity of electromagnetic waves. Had the meter been slightly shorter it could have resulted in a numeric value for the velocity of electromagnetic waves being 314,159,265 meters/sec. What effect would such a numeric value have had on our "measurement system" and its use in formula dealing with physical law?