[quote=@Xaltwind]

[@Expendable]
There's no set standard for tomes, and they're really only called that because fancy wizards and sorceres with big egos are the ones who wrote them. They're just 'books' really. And as for an entire book being needed for, and to learn, a single spell? Suspension of disbelief is my answer there.
[/quote]

I rather like the line idea, where you have a master and a student, and the first spell the student learns is "copy" and they spend the next several days copying everything in their master's spell book. The master gets them started, teaching them the basics, then leaves. The student then has to study hard to unlock the spells they wrote in their own book, needing to learn how to do the small stuff first before trying to tackle the larger spells. 

Sort of like learning as a novice how to summon flame, lighting a candle with your magic, and eventually with a lot of study and practice, you can cast a fireball.

Or starting levitation by making a feather move about the room - then as it passes over an open book, it suddenly snaps shut, trapping the feather. Eventually you can levitate a broom or a carpet as you ride it.

The drawback is if you know what line they belong to, you know what spells they can cast. 

And eventually, they take a student and it starts all over again.

Are you happy with the sheet?