The Ancient Book of Spells is a book that once belonged to Harriet.
In "Spell It Out", Lucy found the book inside of an old chest belonging to Great Grandma Harriet, and tried to use it against her siblings. The book contains descriptions of various spells.
"Eye of newt and toe of frog, Cease this endless dialogue!"
Causes any conversation the target is happening to abruptly end. Lucy used this spell on Lori after her spirit summoning was interrupted, which in this case disabled Lori's phone. In reality, the phone had a flat battery and needed recharging.
"Lizard's leg and howlet's wing, Bring vengeance with an itchy sting!"
Causes the target to develop a painful itch in their butt. Lucy used this spell on Lana for stealing her spot on the sofa. In reality, Lana had previously rolled in poison ivy and developed a nasty rash.
"Gall of goat, slips of yew, Turn clumsy fingers into glue!"
Causes the target to develop literal sticky fingers, getting stuck to everything they touch. Lucy used this spell on Lisa after her poetry book was destroyed by the latter. In reality, the stickiness was due to one of Lisa's experiments, which she had accidentally spilled.
"Round about the bedrooms go, On their pillows, spell dust throw, By sunrise, they will have no choice, But to listen to my voice."
Renders the target completely mute. Lucy cast this spell on all of her siblings so they would not walk all over her. In reality, they had lost their voices from cheering for Pop-Pop during his shuffleboard match.
"To put the spell back on the shelf, Transfer the effects onto yourself."
Removes any spell cast upon a target at the cost of being transferred to the original spellcaster. Lucy intended to use this to undo the aforementioned spells after seeing how badly they were effecting her siblings, but never went through with it after discovering what had actually happened.
The beginning of the first three spells are in reference to Act 4, Scene 1 of Macbeth.