The dip or groove in the middle of a sword blade is commonly referred to as a fuller. The fuller, also known as a blood groove or a channel, is a long, shallow groove that runs along the blade's length.
Fullers serve several purposes:
- Weight Reduction: Fullers help reduce the weight of the blade without compromising its strength. By removing excess material from the sides of the blade, the sword becomes lighter and easier to handle.
- Structural Reinforcement: Contrary to popular belief, fullers do not necessarily make the blade weaker. They can actually increase the blade's rigidity and strength by distributing the force of impact along the spine and edges.
- Sound and Visual Effects: When a sword is swung or drawn through the air, the presence of a fuller can create a distinct sound, often described as a "ringing" or "singing" sound. Additionally, the light reflecting off the fuller can create visual effects, enhancing the sword's aesthetics.
- Historical and Stylistic Elements: Fullers have been incorporated into sword designs throughout history for stylistic and aesthetic purposes. Different cultures and time periods have varying preferences for the shape, length, and number of fullers on their blades.
It's important to note that not all swords have fullers. Some blades, such as those with a straight, double-edged design, may not feature a fuller. The presence and design of fullers can vary depending on the specific type of sword, historical period, and regional styles.
