THE CLOSING of Bartleby's Bookshop in Bethesda later this month leaves only a handful of local secondhand bookshops that seem to give much thought to what goes on their shelves. The contrast with the better new bookshops in the area is particularly striking. Why have Washington's used bookstores, as a group, been reduced to such a sad state?

The ideal of a secondhand bookshop is not hard to construct: It would be open seven days a week (no one who wakes up in the morning and wants to spend a day in a bookshop should ever be denied that right). There should be a core of at least half-a-dozen subjects where a specialist, or at least a sincere autodidact, would find a selection of out-of-print books to rival all but the best of the specialty catalogues, with a generous sprinkling of fine books in several other categories. The review copies would be the better new releases, only at 40 or 50 percent off the list price. The remainders and reprints would flesh out the stock with books that would otherwise be unobtainable.

Nor would the ideal shop be limited to academic interests. Children's books and cookbooks, especially the classics, would be only the most noticeable sign of this. Another would be the large offering of older magazines from the period when the magazine was the focus of a far higher portion of America's creative energies than it is now. In such a shop, people whose curiosity had not been completely drained by modern life would find something which took them beyond themselves. They would recognize, intuitively and immediately, that here was a place even more important to the community than to the owner. Its motto would be that of Christopher Morley's Haunted Bookshop: We have what you want, though you may not know you want it.

Such is the ideal, envisioned by many and realized by nearly none. The reality is far more likely to be either a sort of secondhand version of a discount new-bookstore, aimed at the lowest common denominator of reader, or the quasi-neighborhood shop with neither the capital, the energy nor the imagination to go much beyond that. These are often interesting to visit once or twice but one soon gets the feeling that the stock rotates about once every five years, and that their existence owes more to a favorable lease than to anything else.

Yet even the best shops find it difficult not only to keep up their standards, but even to keep their doors open. More and more are either closing to transform themselves into mail-order catalogue services (as Bartleby's itself will do) or re-opening on a vastly reduced scale. There are many reasons for this, but the two most important are: too few good books out there; and too much competition to get them. Better out-of-print books, most of them published in small editions in the first place, are seldom offered for sale to bookshops by private individuals. My own shop, Georgetown Book Shop of Bethesda, probably gets 50 calls a week from people offering to sell books. In a great -- not good -- week, I may be able to buy 100 books each (counting paperbacks) from three of them. On the other hand, I could fill my 1,930-square-foot shop to the roof with National Geographics and popular fiction every month if I were to buy everything offered to me in those categories.

The result is that in order not to embarrass myself or insult my customers, I am forced to spend a good two months of the year flying and driving all over the country, trying to pick stock off other bookshops' shelves for resale in my own. You can imagine what this does for one's family life. John Thomson, the owner of Bartleby's, only half-jokes when he says that his children, ages 9 and 4, know him mainly by his picture on the refrigerator. Little wonder he decided to switch to cataloguing his stock for mail order -- but at what a loss to Washington!

Remainders -- or the relative lack of good ones -- form perhaps the most frustrating category of all. Book buyers may remember such great emporiums as the Marboro Book Shop in Greenwich Village, which from the '40s to the '70s sold hundreds of fine titles at a fraction of their original cost. In the late '70s, Marboro branched out into wholesaling, and for about three glorious years, independent shops around the country could get a sampling of what New Yorkers had enjoyed for decades. That lasted until 1980, when Marboro was swallowed by Barnes and Noble. The trade edition overstock titles -- the books most people think of as remainders -- are almost wholly sold through the Barnes and Noble retail catalogues and in a handful of their Barnes and Noble stores in the Northeast.

About the only major outfit left that sells real remainders -- as opposed to reprints -- is Daedalus Books in Hyattsville, and even here we find more and more titles being sold only through the Daedalus retail catalogues, or to big university co-op bookstores. This is all done for sound economic reasons, but it puts the smaller independent shops at a serious disadvantage.

I won't mention overhead expenses except to note that when Bartleby's lease came up for renewal, the landlord wanted -- in the midst of the biggest real estate slump in a decade, and with a Montgomery County commercial vacancy rate of 16 percent -- to raise its rent!

The story described here is, of course, one of the inevitable disappearance of the secondhand bookshop as we have known it, or at least as we have idealized it. Catalogue dealers, with their low overhead, may well thrive, as may a few shops where the owners either have other sources of income or had the capital and good fortune to buy their property before the '80s. All this may matter to only a minute fraction of the public, but I suspect it is that part of the public which acts as a leavener wherever it goes. I remember the pain I felt as a 16-year-old when Calvin Griffith took his ball club to Minnesota. The ache I feel now is no less at the departure of Bartleby's.

Andy Moursund has owned the Georgetown Book Shop since 1984.