Spell Books - Size, Pages, Binding, and Scribing
by Lance DuncanFirst off I don't think the outrageous size is a mistake. It reinforces the need of the m-u to memorize spells and and not carry the book with him. The large sack is literally the only container that can hold a spell book.
I did a bunch of research into weights of pages and stuff for my rules awile ago, the weight of parchment is really very variable and so is wood. Here are finalized my rules if you're interested:
"Grimoires(Spell Books): Magic Users keep a library of their grimoires hidden and well protected.
Number of spells: A Grimoire contains the arcane background, history,incantation, and
necessary binding formulae of a single spell.
Size: Grimoires are 2’x2’ and vary in thickness, weight and page count per spell level
1st = 300 leafs of parchment, 320 cn, 2 inches
2nd = 400 leafs, 420 cn, 2.5 inches
3rd = 500 leafs, 520 cn, 3 inches
4th = 600 leafs, 620 cn, 3.5 inches
5th = 700 leafs, 720 cn, 4 inches
6th = 800 leafs, 820 cn, 4.5 inches
7th = 900 leafs, 920 cn, 5 inches
8th = 1000 leafs, 1020 cn, 5.5 inches
9th = 1100 leafs, 1120 cn, 6 inches
Beginning Grimoires: Magic Users have scribed two grimoires at first level, Read Magic,
and another of their choice
Scrolls – Arcane spell casters may write the incantation of a spell that is held in their
mind(from a grimoire they have onto a scroll (weighing 1cn per spell level) to be preserved for a
casting at a later point in time."