First published in 1912, this is the second edition of what would, by 1976, become a series of thirteen separate, and ever-expanding, versions of The Victrola Book of the Opera, a wonderfully illustrated tome detailing every operatic record released by Victor records. As the Library of Congress explains:

The Victrola (or Victor) Book of the Opera was an ingenious strategy to promote sales of Victor label discs of opera excerpts. For 75 cents, record buyers could learn the plots and production histories of the most popular operas of the day, enjoy illustrations of favorite singers in costumes, and most importantly, have in hand a list of Victor records, with catalog numbers, of excerpts from each opera. Early editions of the Book of the Opera were compiled by Samuel Holland Rous, the editor of Victor sales catalogs. Rous began his career with the company as a tenor vocalist on many early recordings, billed as “S. H. Dudley.”

And from Rous' own mouth courtesy of the foreword to the original 1912 edition:

During the recent season several hundred performances of grand opera, at an estimated cost of millions of dollars, were given in the United States. This great outlay for dramatic music alone would not have been possible had it not been for the increased interest aroused in opera by the widespread distribution by the Victor during the past ten years of hundreds of thousands of grand opera records, at varying prices… For every person who cannot attend the opera there are a hundred who cannot. However, many thousands of lovers of the opera in the latter class have discovered what a satisfactory substitute the Victor is, for it brings the actual voices of the great singers to the home, with the added advantage that the artist will repeat the favorite aria as many times as may be wished, while at the opera one must usually be content with a single hearing…

When you've done browsing through the above, we highly recommend taking a visit to the Library of Congress site where they've a wonderful interactive digital facsimile of the 1919 edition, including the opportunity to listen to nearly every recording listed in the book.