hummm.... too bad we don't have Sarah Palin on here!

There really is no good way to measure it. The stock market was functioning and it was gaining strength in terms of activity. But the Dow theory and averages as a way to measure the market came a little more than three decades later.
The Alaska Purchase by the United States from the Russian Empire occurred in 1867 at the behest of Secretary of State William Seward. The purchase price set at $7,200,000 (about 1.9¢ per acre).
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There really is no good way to measure it. The stock market was functioning and it was gaining strength in terms of activity. But the Dow theory and averages as a way to measure the market came a little more than three decades later.
The Alaska Purchase by the United States from the Russian Empire occurred in 1867 at the behest of Secretary of State William Seward. The purchase price set at $7,200,000 (about 1.9¢ per acre).
The purchase was at the time derided as Seward's folly and Seward's icebox because it was believed foolhardy to spend so much money on the remote region. There were no investment opportunities and it probably did not have much effect on the price of other investments. Our currency was impacted in a minor way. The Russians needed the capital badly.
There were wonderful speeches by government officials about what a great deal it was. Just the same as today.
The free market soon had things valued more correctly, perhaps a little undervalued.

Your nine year old son sounds remarkably bright. I predict a wonderful future for him.