The French say, "The more things change, the more they remain the same."

So it is, of all things, with fishing.

This unexpected insight comes after perusal of a 1941 book that kept the unemployed writers of the capital city busy during the Depression. The treatise, Washington Angler's Guide: Fishy Facts for Amateurs & Addicts , was saved from extinction by the Library of Congress, which saves everything.

This funny little book runs the gamut from great piscatorial insights to pure hogwsh, which makes it your standard fishing book. If it kept writers from starving, more power to it, even if they did manage to get the letters fouled up and send people out into the Chesapeake Bay after "gay sea trout" (that's "gray," fellows) and "cabio," which must be a Spanish cobia.

While they got a few things wrong the Work Projects Administration writers also managed to save for history some layman's facts about the nature of the marine life two generations ago. A lot of it sounds very familiar.

To wit: "Chain Bridge, for many years a favorite rendezvous of anglers, offers a chance for bass, perch, catfish and, in the early spring, herring and rockfish. At Joe Fletcher's, on Canal Road between Chain Bridge and Key Bridge, the fisherman may obtain bait and up-to-the-minute information on the biting."

"That was my granddaddy," said the current Joe Fletcher, who runs Fletcher's bait, boats and up-to-the-minute information headquarters on Canal Road between Chain and Key Bridges.

Granddaddy Fletcher was dealing with much the same resource as his son's sons are today. Perch, herring, catfish, bass, rockfish and a few shad still begin feeding voraciously near Chain Bridge in the spring.

The 1941 Angler's Guide says, "White perch arrive (on their spawning run) between April 1 and 15, depending on water temperature." The current Joe Fletcher, busy painting boats his father and grandfather built, took a long look at the river the other day and said, "March 25," his guess for this year's arrival date.

There's even good news in the old book, which paints a grim picture of water quality around the city, a picture that has changed for the better in the intervening four decades.

"Because of the heavy pollution nearby stretches of the Potomac, Tidal Basin, old C&O Canal and Rock Creek the editors . . . strongly urge anglers to avoid these waters," said the book.

Yet within the next month anglers will be hoisting crappies from the Tidal Basin, netting herring in Rock Creek, catching bass in the Canal and perch in the Potomac and taking them home to eat. Maryland coldwater fisheries specialists have even considered stocking trout in Rock Creek for put-and-take fishing, a plan that was unthinkable before tighter sewage laws revived the creek.

The news is a little less positive about the Chesapeake, compared to 40 years past. In those days fishermen had a broader choice when they made the hour-long drive down dusty two-lane highways to Rosehaven, Chesapeake Beach, Deale, Galesville or Herring Bay. They could bottom-fish for croakers and spot, two species that since have all but disappeared from the upper stretches of the Bay.

But the rockfish, bluefish and gray sea trout remain, and techniques are much the same.

"Trolling has been found to be the most successful method of catching rock and blues," says the guide, "while the smaller species seem to prefer the baited hook." So it is today.

Ah, yes, the more things change, the more they remain the same.Even 40 years ago, the editors of the guide knew where to turn for quality information on what was biting where. To the newspaper, of course.

"The writers who so ably handle these (fishing) columns take special pains to keep in touch with various informants throughout the adjacent territory," says the guide. "Their information is always current, and if their printed columns do not supply your needs (heaven forfend), the writers will. Call them.

"The editors of this guide . . . refer you to them with full confidence. . ."

Well said.