Other nostalgic memories regarding that book: (c1964)
There was a Tardis.
Where is the Tardis?
I WANT THE TARDIS!!!!
I was reading that book when my Dad told me some people, in countries where there were few books, had to read upside-down, and that it was easy to read books upside-down.
He was right! I have been able to read upside down rather easily ever since...