The Panic of 1873 was a financial crisis that triggered a depression in Europe and North America that lasted from 1873 until 1879 (1897 (!) in Britain)---6 years.

The 1882-1885 depression included a year when "an estimated 5% of all American factories and mines completely shuttered during the 12 months running from July 1, 1884, to July 1, 1885".

The panic of 1893 included a depression that extended to 1897, a couple of years with 12-14% unemployment, with peaks somewhere around 17-19% and 25% in Pennsylvania, 35% in New York, and 43% in Michigan, and included the panic of 1896.

Keep in mind two things: these occurred in the 19th century, when the United States was largely, perhaps almost completely an agrarian country, and that when banks fail (a common occurrence in many of these), you don't get your money back out.

The Great Depression is called that because it was the biggest, but it was hardly a completely new and unique thing.

[Now, as to Austrian economics, if "it is deductive from pure logic, rather than from experimental or statistical observations", I would think it had more in common with mathematics than either biology or psychology. Or perhaps alchemy.]