According to the Wyoming Historical Society, on April 18, 1890, the National Land and Livestock Co. was incorporated with a capital of $250,000. Also on April 18, but 5 years later, E.T. Payton launched his second newspaper, the Big Horn River Pilot, in Thermopolis. On April 20, 1868, the Union Pacific Railroad began selling lots for the new town of Laramie, Wyoming Territory. Also on April 20, but in 1920, novelist and newspaperwoman Caroline Lockhart and friends founded the Cody Stampede. Again on April 20, but in 1932, sodium exploded in a Thermopolis high school chemistry class, injuring seven students and the instructor. On April 21, 1868, an early issue of the traveling newspaper the Frontier Index was published in Laramie, Dakota Territory. Also on April 21, but in 1896, the Eastern Shoshone and Northern Arapaho tribes approved the sale of 64,000 acres including the hot springs at present-day Thermopolis for $60,000.