It's the Singer Sewing Book - A Complete Reference Guide to Sewing. It was printed in 1961, right around the time my Slant-O-Matic 503A was born so I had to have it.
It is an excellent resource for all things sewing. It gives very clear instructions about how to use attachments and about different sewing techniques.
Below is an excerpt from the book:
I love how they talk about how to treat your sewing machine. I think I'll have to make a cover for mine.
If you ever see it for sale snap it up. It's a great reference. You'll be glad you did.