The Foley and Burk Carnival was a west coast operation. According to Joe McKennon's " A Pictorial History of the American Carnival, Volume II," they were in operation from 1913 till 1969.
They donated one of their Warren flatcars to the Circus World Museum for the Schlitz Circus Parade train. Used in 1972 and 1973, it went on the train carrying the Foley and Burk title.
1973 was the last year for the parade for several years. Although a couple parades occurred in Chicago and Baraboo, the parade was resurrected with the movement by the CWM train again in 1985. The Foley and Burk flatcar was repainted and re-lettered with the Ringling Bros. and Barnum & Bailey title.
I'm guessing these 5 photos were taken around the 1950's or early 1960's.