were sitting behind him playing horse, and whipping him to giddap
." In their poverty the family "pawned everything at one time or another, including the children's shoes and Marx's coat--which prevented them from going out of doors." It sometimes got so bad that his wife "would cry all night, and Karl would lose his temper: he was trying to write his book on economics." There's a humorous flourish about this final sentence, in which the immediate economic hardships frustrate Marx's attempts to complete Das Kapital, his magisterial study of the economic force in history.
When they got to the gate the light was red, but the policeman ignored it and shouted "giddap
" to the horse and drove on through the red light.