The Gas Engine and American Machinist note that various models were available, but not illustrations of the Monarch engines can be located. Monarch vertical engines can be located. Monarch vertical engines were buildt in 1 1/2 and 2 1/2 horsepower sizes. Single cylinder horizontal engines were built in eight sizes ranging from 2 to 20 horsepower, with farm portables being available in a range from 2 1/2 to 15 horsepower. Large two sylinder horizontal stationart models were also built in sizes from 25 to 100 horsepower.