The Federal Reserve was founded in 1913. The dollar has lost roughly 97% of its purchasing power since.
In 1913, a dollar bought a sit-down dinner. A pair of leather work boots ran $3. A new Ford Model T sold for $525. The same dollar today — the same green paper — buys a soda from the bodega, sometimes.
Measured in gold, the picture is sharper. In 1913, gold was fixed at $20.67/oz. So $1 represented 0.048 troy ounces of gold. At today's spot price, that same physical amount of gold sells for hundreds of dollars.
The dollar didn't change shape. The number of them changed. Gold, silver, and copper sat still while the printer ran.
Sources: BLS CPI Inflation Calculator · gold price: London PM Fix.