A tour de force of primary source research, this volume is a comprehensive encyclopedia of First World War naval weaponry. In his introduction, Friedman makes it clear that while his book contains information researched by the late John Campbell, whose similarly titled work on the naval weapons of World War II is the gold standard for the subject, this book is primarily of Friedman's own research and authorship.

The book is arranged in four parts by naval weapon: guns, torpedoes, mines, and anti-submarine weapons Within each part, weapons are arranged by country. Each weapon type is arranged seperately. For guns and torpedoes, arrangement is by caliber. For mines and ASW weapons, arrangement is roughly chronological by weapons development. At the beginning of the book the author provides a brief introduction covering naval weapons in general. Each major country then has its own introduction in each part that provides much greater detail specific to the country.

As Great Britain's Royal Navy was the greatest naval power in 1914, its entries in all four parts are the largest and most detailed. Great Britain's position as the greatest naval power also translated into world leadership in the shipbuilding, steam engineering, and ordnance industries. The Royal Navy leveraged that leadership into an intelligence asset. Major ordnance companies such as Vickers and Elswick made their foreign order books available to the Royal Navy's intelligence apparatus, so it was very well informed about foreign navies' capabilities, a happenstance of which Friedman was able to take advantage in his research.

The quality of books of this type are very dependent upon the availability of source material, so how each nation preserved its naval records is very important. This is obvious when one compares the page counts of the specific national entries. For example, the section on British guns spans a full 104 pages, that for Germany 27 pages, for the United States 50 pages, for France 32 pages, for Italy 14 pages, for Russia 22 pages, and for Japan 34 pages. It is easy to see that those countries that had not been occupied by a conquering power would retain the greater percentage of their naval records.

I was happy to see that Friedman made use of the large Bureau of Ordnance Ordnance Pamphlet series in the National Archives for the U.S. sections of the book. That record series was still classified as late as 2003 and unavailable to researchers. I was able to process the series for declassification many years after it should have been done. I am glad to see that a researcher could make good use of those records. ( )