In Frankenstein, what did Robert Walton read for 14 years of his life?

You can find the answer to this in the second letter in
the book.  It is dated 28th March and is written from
Arkangel.

In this letter Walton is writing to his sister
Margaret.  He is talking, in part, about regrets he has about his past and the way his
past affects him now.  This is the part where he tells what he read during those 14
years.

He says that he was completely self educated and all
he ever read was his Uncle Thomas' "book of voyages."

This
distresses him because he is now 28 but is less educated than kids who are half his age
but who have had proper educations.