Giacomo di Grassi was an Italian fencing master who wrote the fencing treatise Ragione di adoprar sicuramente l'Arme, si da offesa come da difesa in 1570. The text was later translated into English and published again in 1594, as DiGrassi, His True Arte of Defence. The translation of Di Grassi was one of the three premiere fencing texts known from Elizabethan England.
His main teachings were that weapons of the same length are used similarly, the thrust is preferred to all other attacks, as well as specifics on how to thrust and handle specific weapons.
Digrassi wrote at a time of transition from heavier swords to longer lighter swords such as the rapier. The illustrated posture and footwork style is erect, front facing, with feet close together; similar to modern Kendo footwork but unlike that advocated by some 17th-century authors of the subsequent generation.
Swords and spears, when used to fight at close quarters, both work on the same principles. They are bladed weapons, with handles of varying lengths. What is important to keep in mind when using these is their length. There are three lengths, which determine how they are held and used: short, medium and long. Short, like a single-handed sword, means about half the height of the user. Medium, like a two-handed sword or a short spear, means about the height of the user. Long, like a pike, means significantly taller than the user.
For all weapons, the straight thrust forward is the quickest method of attack, puts the least amount of stress on the weapon of any blow, and if the tip is pointed, provides the easiest method of piercing into the body.
To thrust it forward, the weapon must be jabbed ahead, with the arms alone, a step forward, a lunge-step, a jump, a run, or any combination or stringing together of these.
To get maximum reach and to make the body as flat as possible to the opponent to dodge a counter-thrust, at the end of the thrust the back foot is shifted diagonally forward so that it is in line with the front foot and the tip of the weapon. It should be noted here that the final diagonal step also brings the body out of the direct forward thrust-path of the opponent, achieving an angular attack and evasion both at once.
The following three actions can be practiced as drills in basic ancient weapon handling, if you are healthy enough to try them, if you have enough space to safely perform them, and if you have sticks of varying lengths to use.