Examples from the Web for ferrum
In ferrum pro libertate ruebant—They rushed upon the sword in defence of their liberty.
Germans (apud Tacitus) called their iron lances “framea,” which has great resemblance to ferrum.Tradition|John Francis Arundell
Prterea magnes trahet ferrum, sive potius magnes & ferrum ad invicem accedunt, neque enim ulla ibi tractio est.The Works of Sir Thomas Browne (Volume 1 of 3)|Thomas Browne
At ferrum, quod pluit in Taurinis, cuius frustum apud nos extat, qua ex fodina sustulit nubes?On the magnet, magnetick bodies also, and on the great magnet the earth|William Gilbert of Colchester
The forms in "f" appear to indicate a derivation from the Latin "ferrum," iron.On the Development and Distribution of Primitive Locks and Keys|Augustus Pitt-Rivers