As most Hogarth's books, this one is not at the least descriptive. The drawings are a bit more frequent, and you may find it useful. The author provides 4 decent approaches to the illustration of wrinkles in different situations, mostly differenting dependent on the type of physical movement the character (human, in all cases) makes. Most of the book talks about drapery, but there is some information on how to apply the same principles onto skin.
This is a must-have for a character designer, whether you work in 2D or 3D. It will provide a beginning artist with the basic understanding of the dynamics of drapery and clothes, but it won't be much use for a medium-to-experienced studio artist, especially when she/he draws from life.