This is a good description of what the classical gold standard was, and the difference between the classical gold standard before World War I and what emerged after World War I. From Joseph T. Salerno at mises.org:
The historical embodiment of monetary freedom is the gold standard. The era of its greatest flourishing was not coincidentally the 19th century, the century in which classical liberal ideology reigned, a century of unprecedented material progress and peaceful relations between nations. Unfortunately, the monetary freedom represented by the gold standard, along with many other freedoms of the classical liberal era, was brought to a calamitous end by World War I.
Also, and not so coincidentally, this was the “War to Make the World Safe for Mass Democracy,” a political system which we have all learned by now is the great enemy of freedom in all its social and economic manifestations.
Now, it is true that the gold standard did not disappear overnight, but limped along in weakened form into the early 1930s. But this was not the pre-1914 classical gold standard, in which the actions of private citizens operating on free markets ultimately controlled the supply and value of money and governments had very little influence.
Under this monetary system, if people in one nation demanded more money to carry out more transactions or because they were more uncertain of the future, they would export more goods and financial assets to the rest of the world, while importing less. As a result, additional gold would flow in through a surplus in the balance of payments increasing the nation’s money supply.