Unfortunately, Hidden Channels of the Mind is neither a provocative look at ESP/Psi, nor is it a particularly rigorous look at the phenomenon, but seems to float in a middle ground, with a formal structure, but heavily based on unattributed "stories", many of which reminded me of those Angel books I read a month or so back! I hate to just walk you thought the contents page, but "cherry picking" some highlights might well be the best way to show where the author was going in this book. She discusses "Types of Extrasensory Perception", divided into "from other minds", "from mindless objects" and "from the future", then looks at the "Forms of ESP Experience" which she splits into "realistic", "unrealistic", "hallucinatory" and "intuitive". A section looks at space and time, another looks at the difference of how men and women perform in lab tests, and another looks at performance across various age ranges ... again, these would be a lot more interesting (to me at least) if they focused on the lab results, but they're primarily stories of so-and-so "seeing" such-and-such, but none in a lab setting. The second half of the book is largely set on precognition, with a whole section looking at whether one can or can not avoid "foreseen" events ... unfortunately, here too, the bulk of the "evidence" is tales of distraught mothers/wives wondering if they could have "done something" (or tales of them having prevented loved ones from "getting on that train", etc.) ... needless to say, this sounds pretty weak nearly fifty years down the road.
This is not to say that the book is not worth a read, it's just not the book I'd hope it would be ... if the Rhines had taken the "scientific rigor" that Hynek applied to his UFO studies, ESP might have had a more solid foundation to grow on, but if all their work depended on the sort of "evidence" that's presented here, it's understandable why Parapsychology sort of faded away as a "respectable" field of study!
While this one is officially out of print, the Amazon new/used vendors have "like new" copies available for under a buck ... and given that these are such swank editions (silver edging, purple ribbon book marker, etc.), you might want to snag one just for the heck of it.