Check an iBook I'm making on a Mac? I'm making a book with iBooks Author, for the iBookstore.

It's a simple picture book; each page an image. No video. No sound.

I don't have an iPad or an iPhone.

Is there a way to check how the book is working, without using an iPad? – just on my Mac.

(I'm running OSX 10.8.5. on a MacBook Air.)
No, not until you can install OS 10.9, which will have the iBooks app.  Until then, books created with iBooks Author can only be read on an iPad (not an iPhone or any other platform).  If you want a book which can be read on all platforms, you need to use the .epub format.  iBooks Author cannot produce that, but Pages can.