The Expert at the Card Table is one of those books that comes up in every discussion about "getting started" in card magic, usually as an example of exactly where you shouldn't start. The book is hugely influential, but also enormously intimidating and difficult to follow, as Jason England explained quite eruditely in the above interview.
Originally released as Artifice, Ruse and Subterfuge at the Card Table: A Treatise on the Science and Art of Manipulating Cards back in 1902, the book is considered required reading for any card manipulator with aspirations of quality. It was written - by pseudonymous author S. W. Erdnase, whom magic historians have thus far failed to identify - as an accessible guide for the amateur cards man. It may have served that role well over a century ago, but Expert has largely been replaced with more accessible texts like Hugard's The Royal Road to Card Magic, which was quite obviously inspired by it. Talking about Expert, Hugard once said, "... perhaps no other book in all the list of conjuring books has been so avidly read, so affectionately regarded."
Many fledgling magicians in this day and age ask why they should learn magic from books at all when quality video tutorials are just a search on YouTube away. The answer is quite simple. There's a wealth of techniques, many of which may have vanished completely from the current industry, to be found in dusty old volumes on performance magic. The ability parse the dry text of Victorian magicians and perform their tricks today is vital to any magician who wants to remain competitive. In essence, books like Royal Road and Expert teach you how to read magic, and that's a fundamental skill.