For anyone who has come through the lottery of Art College education over the past few decades this book may answer some important questions about how to actually paint successfully in Oils. Without being pedantic the author shares his considerable experience as a painter, laying out in an ordered fashion methods and stages in development of painting. It is a practical book written for people who would like to be told straightforwardly how various masters have worked, their techniques, colours, methods.
This is the kind of book that speaks confidently and with a certain authority about the craft of painting, mainly prior to impressionism (but not wholly). Some might regard the style as pedantic and moribund. However I think that, for the time, the style of writing is warm and even humorous. You are free to take what you need from this useful volume without needing to feel compelled to agree with every statement Harold Speed makes. Many of his observations on the studio methods of artists such as Rubens, Gainsborough, Turner (and many more) are cogent and enlightening. Particularly useful is his understanding of Transparent and Opaque pigments, Warm and Cool colours and the descriptions of artists' palettes.
I find that I 'dip in' to this book often, sometimes just idly opening it at a random page and reading; and I'm always rewarded. And I often find that I can use some of his painting tips straight away.