Amassive number of people selling their stocks all at once led to what day?

Black Tuesday, 1929, which was the spark of the Great Depression

there is no chart here so no one can answer this.

frederick william of brandenburg-prussia trained his son, frederick, to be a hardy soldier. but frederick disliked rifle shooting and horseback riding. unlike his father, he was interested in french literature. he enjoyed poetry and music and, like some others of the enlightenment, he scoffed at religion. his father thought him soft, frivolous and unmindful of his duties. and when frederick refused to put his signature on a right to succession, for a few moments his father strangled him.