Arcane items are items that enhance a Wizard's magical powers in some fashion. Only a Wizard can carry an arcane item and no character can carry more than one.
Scrolls are a type of arcane item that contain powerful enchantments that enable Wizards to manipulate the power of magic. They are useful aids to spellcasting and to resisting an enemy's spell. Unlike other arcane items, there is no limit on the number of scrolls a Wizard can carry, other than the total points value of magic items he is permitted. Wizards can have one arcane item as well as carry several scrolls (of the same or of different type).
Once a scroll is read, it crumbles to dust or its writing fades to nothing. Each scroll can therefore only be used once during the whole battle.