Dr. Lyman J. Briggs, director of the United States Bureau of Standards, wants to shorten the inch. It is too long, he says, and furthermore, the difference between the length of the inch in this country and in Great Britain “is intolerable.”
In line with Dr. Briggs recommendation, the House Committee on Coinage, Weights, and Measures, has reported out a bill which would fix the length of the inch and the weight of a pound. The bill proposes to establish the inch to equal 25.4 millimeters exactly. This would shorten the inch by two parts in a million. It is now 25.40005 millimeters, as against 25.39996 in Great Britain.
Dr. Briggs, in urging the legislation, hastened to assure industry that the change would not be disturbing.
“I wish to emphasize,” he said, “the fact that the change will not disturb industry in any way. Industry, from a practical standpoint, will not realize that a change has been made, because the change is too small; it is far within the limits of tolerance permitted in making industrial measurements.”
Note that this was in February 1938. Note that this proposal must have gone through, for in the US an inch is still defined to be 25.4 millimeters (to be precise, 1/36th of a yard, which is 0.9144 meters. This definition was standardized on July 1, 1959 (so the 1938 proposal took a long time to be adopted). Given that a meter is defined as the length of the path traveled by light in vacuum during a time interval of 1/299,792,458 of a second, this means than an inch is, oh, you do the math!.