Irving Fisher,
The Purchasing Power of Money…
“ A bimetallic level, therefore, when bimetallism is feasible, must always lie between the levels which the two metals would have assumed under gold monometallism, gold being currency and silver not, and for the same reasons it must lie between the levels which the two metals would have under silver monometallism, silver being currency and gold not.*75 In all our reasoning we have supposed a given legal ratio between the two metals. But bimetallism, impossible at one ratio, is always possible at another. ”
