Complex sentence: The return of silver dollars to the West Indies after 1873 threatened the gold standard there that had been in operation since 1704, and so by the year 1876, the British West Indies territories began to pass legislation to demonetize the silver dollars.
Split into simpler sentences: The return of silver dollars to the West Indies after 1873 threatened the gold standard ther, which had been in operation since 1704. By 1876, the British West Indies territories began to pass legislation to demonetize the silver dollars.