American wire gauge - why exactly this ratio?

Wikipedia on American wire gauge reads:

Any two successive gauges (e.g. A & B ) have diameters in the ratio (dia. B ÷ dia. A) of $\sqrt [39]{92}$ (approximately 1.12293), while for gauges two steps apart (e.g. A, B & C), the ratio of the C to A is about 1.12293² = 1.26098.

My question is: why exactly this ratio? What's the background behind it?

• Since the gage number follows a geometrical progression of successive diameters (1.123) and the ratio of every six gage it is also standard (nearly 2), it is relatively easy to calculate resistance, mass or cross section deducting from the next. So every three gage the resistance, mass per length and cross section doubled or halved. – GR Tech Jan 16 '15 at 19:25