1875 Southwest Tornado outbreak
1895 Kansas-Iowa Tornado outbreak
1929 Rye Cove, Virginia Tornado Outbreak, 44 people are killed.
1939 Kopet Dag Earthquake shakes the Iran-Turkmenistan border region with a maximum Mercalli intensity of IX which is violent, killing up to 3,800 and injuring 1,121 people. (It is a 7.2 Mw
Mw is the moment magnitude scale. The w stands for work. Mw = 2/3 log10 (Mo) -10.7 where Mo is the seismic moment in dyne cm.