"Acho que deberias ver o meu album de Historia de Roma, procurao como 1ESO A cidade Romana."

"A reconstructed, complete ballista of the Ermine Street Guard in the UK (Legio XX Valeria Victrix), on display at Birdoswald Fort (Hadrian’s Wall) in May 2007. Although only loosely strung, this ballista fired a stone ball 30 to 40 yards, reaching a very great height."

"Above is a reconstructed, complete scorpio of the Ermine Street Guard in the UK (Legio XX Valeria Victrix), on display at Birdoswald Fort (Hadrian’s Wall) in May 2007."

"A photo of a recreated Roman ballista-type 'Scorpion' catapult. In essence it's much the same, but smaller than a basic 'ballista'. However, this machine was devised as a piece of field artillery. Unlike the full-sized ballista which was a siege engine firing stone balls, the scorpio supported Roman infantry on the battle field by firing bolts at enemy."

"The torsion mechanism of the ballista’s right arm. The twisted ropes provide the power which propels the arms; the greater the twist the greater the power."