After reading Tom Gervasi's fine piece on the F-15 fighter plane in the May issue of Harper's Magazine, I expected his book, Arsenal of Democracy, to be more of the same. But it is not a book with a story line at all. Instead, Arsenal is a dictionay of American arms. The definitions are detailed, include the prices of the weapons, and often reflect the author's personal opinions. It is really a book for defense specialists who will probably put it on the same shelf already weighed down with the heavy volumes of the Defense Marketing Service reports and Jane's various reference works on weapons.

I did not read Arsenal from cover to cover, and I doubt if anyone could -- any more than one could read a dictionary all the way through. Perhaps this brief sample from the book will illustrate why it is not exactly bedtime reading, but certainly informative:

"M-18A1 Claymore Anti-Personnel Mine: Developed by the Picatinny Arsenal, the Claymore Mine is an RFD (Remote Firing Device) that was heavily used in Southeast Asia, and successfully copied by the Viet-Cong. Weighing 3.2 lbs, it consists of a rectangular case of polystyrene and fiberglass curved outwards to cover a forward front of 60 degrees, with a charge of 1.5 lbs of Composition C-4 explosive. In Service Abroad: Israel, United Kingdom, Vietnam and West Germany. Price: $119 (1978 open market price)."

Gervasi, who is described on the book jacket as "a former counterintelligence officer assigned to the Army Security Agency" and "an editor and marketing executive in book publishing since 1961," steps beyond hardware descriptions in longer sections of the book. For example, in discussing the F-15 fighter which President Carter has decided to sell to both Israel and Saudi Arabia, Gervasi states that Carter administration assurances about the difficulties the Saudis would have in training other nations to use the plane "are correct," but adds editorially that "the transfer of F-15s from the Saudi Air Force to another in time of war remains entirely feasible."

In sum, Arsenal is an ambitious undertaking which throws helpful light on the dark world of building, buying and selling deadly weapons in this mad age when the United States and the Soviet Union have nuclear guns pointed at each other's temples. One hopes that Gervasi, on the basis of his massive research, will have more to say in the future. (Grove Press, $19.95; paperback, $7.95)