"There are two types of "private readers" or office clairvoyants. The first and most common are referred to among members of the profession as 'shut-eyes'. Shut-eyes are sincere people who really think they possess genuine psychic power and are able to legitimately divine the future.
The value of their work is sometimes questioned, though, in many instances, they are quite successful and most accurate in their readings.
However, at the outset, the reader of this text should (and rightfully so) assume that certain people do possess a highly developed intuition, psychic power, (or whatever you choose to call it) or ability to frequently foretell future events. The origin or source of this ability is intangible and debatable, but definitely, that ability does exist in some people."
The above text is a quote from the book, "Secret Methods". Nelson draws a picture of what it was in the middle of the 20th Century. Today's facts may differ greatly from those facts!
Today's reality is, of course, much different. However, there are things to be learned from the text. Things such as palming and switching. The use of 'billets' and how to switch them while sitting at a table. As a Mentalist, I would not even try to set up an "office" and do the things and use the ways Bob writes about. However, there is much to be gleaned and a 'fun' read of Bob's writings. I have updated some of the wording and terms or titles are given to people. We now live in a different age.