What Makes a Book Valuable?

I was also asked recently about the most valuable book in our library. Unlike the question about the oldest book, the answer to this question is far more complicated to determine.

 
Among the seemingly most valuable books in the library is a complete run of the Gentleman's Magazine (pictured above), from 1731 to 1868. The age, condition, completeness, and relative availability (or lack thereof) of this set all contribute to its value. In more blatant financial terms, in some cases, individual articles sell for thousands of dollars, while individual issues or volumes can sell for a few hundred dollars each.

With respect to individual works, our library also possesses a copy of Robert Wood's The Ruins of Palmyra, published in London in 1753, a copy of which recently sold in New York for $7500. As is obvious from the picture below, this volume is a precursor of what we would now call a coffee table book, with this one actually being big enough and heavy enough to serve as a coffee table.

Not only is this a big book, but it also contains some big surprises, like the engraving illustrated below. Much of the value of this work is associated with its existence as an expression of material culture.

With both of these examples, an insurance adjuster will want to know the replacement cost, and a rare book dealer will want to know how much a collector is willing to pay for such a work. What does a librarian want to know?

For that answer, we turn to the writings of Indian mathematician and librarian Shiyali Ramamrita Ranganathan (d. 1972), recognized as one of the founding fathers of modern library science. Among his five laws of library science, the first three are: books are for use, every reader, his or her book, and every book its reader. If our copies of the Gentleman's Magazine and The Ruins of Palmyra sit on the shelf and are never used by anyone, are they of any value at all?