 Complete the following phrase:  Luna Park was an amusement park that was in operation in Chicago, Illinois, from 1907 to 1911. Located on the plot of a former picnic grove at the corner of 51st and Halsted Streets, it was owned by an investment group led by boxing promoter James Big Jim OLeary son of Mrs. OLeary of Great Chicago Fire fame. A trolley park occupying only ten acres, Luna Park was smaller than most of the other Chicago amusement parks of the era most notably 