This print, showing a Knight in the 'ancient costume of the Order', was probably from "Histoire et costumes des ordres monastiques, religieux et militaires, et des congrégations séculières des deux sexes." printed in France by Benjamin Jollivet in the middle of the 19th century.
The interesting thing about this depiction is that the Mantle has sleeves and the knight carries a scimitar. It would seem to suggest that this was the Habit of the Order while still in the Holy Land (before the fall of Acre in 1271), though it more likely to be a flight of 19th century fancy! Still, with that sword in his hand this knight certainly means business. He couldn't, of course, be shouting "Atavis et Armis!" since that only became the motto of the Order in 1778.