Not the only instrument to use Pythagorean tuning 

I object to this statement:  "Since Pythagoras calculated the formula for the musical cycle of fourths and fifths, Steel Pans are the only instruments made to follow this configuration."

Surely there have been (many) other instruments designed with pythagorean tuning over the centuries.   Furthermore, it's not even clear to me that (every) Steel Pan's tuning is based on exact 3:2 frequency ratios; in practice I suspect they may often be tuned to 12-TET.