Item description error: Ale Barrel

[DrAtomic1]

Item: Ale Barrel
Type: Artifact (Level 2)
Race: Dwarves

The desription says:
A big belly beer keg.
+1 Morale to all dwarves in the army

Sniper set
-3 Attack, +20% probability of Critical Hit by from arrows
- Ale Barrel
- Telescopic Sight

The issue: it's either by arrows (in which case it grants a 20% bonus to the probability of critical hitting with arrows) or it is from arrows (in which case it grants a penalty where you have a 20% larger chance of getting a critical hit from arrows incoming to you).

Side question: is the bonus/penalty for all projectiles (ie cannons and alchemists as well) or just arrows as stated in the description?