Within living memory, it's said, the White House fireplaces were always perfectly stocked with instant-light fires, so the resident president could settle back on the hottest August day, snap on the airconditioning, flip a match into the hearth and relax before the blaze.

Not everyone is so lucky. Rich folks still have the hired help prebuild their fires, but the rest of us still face the wintry task of starting the ceremonial fire ourselves.

It can be a grim enterprise. Recently I watched a crowed of supposedly earth-wise folks attempt it. They clearly hand't the foggiest notion what they were about. They dragged in half a dozen damp, round walnut longs from the woodshed, piled them happhazardly on the grate, balled up a couple of pages of the Post and fired it up.

It was the world's shortest fire.

I've never been a Boy Scout and I've never been a professional fire-builder for rich folks, but over the years I've picked up a few of the finer points of living-room arson.

Some precepts:

SMALL COMES FIRST. There are geniuses who can stock wood from tinder to kindling to split log all at once and have it work, but for most of us it's advisable to build a miniature fire of kindling first, then add the bigger stuff as it gets roaring.

To build small, first make a loose raft of two handfuls of small twigs and limbs, stacked crosswise with plenty of air space. Stuff a whole section of the weekday paper under it, balled up page by page. The wood will ignite almost immediately.

Let it burn two or three minutes, then add some slightly larger wood, again crosswise layers.When that goes up add hardwood in the same fashion, with the smallest pieces of split, dry hardwood going on first.

A lot of fires are attempted without kindling at all because when people buy firewood they get only logs. Firewood suppliers don't bring small stuff.

You can probably buy kindling somewhere, but it's easier and more satisfying to gather it. Washington is an oak-tree town, and every fall and winter brittle oak branch ends litter streets, woods and yards. I find that if I take a canvas bag along, a walk to the Post Offive yields enough dried kindling for two weeks' fires.

Those who have no access to woods should look to construction (or destruction) sites. Old two-by-fours, split or even whole, ignite in no time.

As the fire grows, add other split pieces toward the back of the fireplace. This should be done according to Precept 2:

FIRE FEEDS UPON ITSELF. Never stack firewood side-by-side or directly on top of another piece. Se it at a 90-degree angle or off to the side a little, perhaps half on top, with air space between any two pieces. That way the flames shoot up from the lower piece, catch an edge of the upper piece and start it burning.

Precept 3 has to do with types of wood:

LIGHT BURNS FAST; HEAVY BURNS SLOW. If a piece of wood is easy to lift, changes are it's soft wood, such as pine or cedar, and it's probably dry. These woods are great for getting a fire started, but they burn too quickly

Thos who have no access to woods should look to construction (or destruction) sites. Old two-by-fours, split or even whole, ignite in no time.

As the fire grows, add other split pieces toward the back of the fireplace. This should be done according to Precept 2:

FIRE FEEDS UPON ITSELF. Never stack firewood side-by-side or directly on top of another piece. Set it at a 90-degree angle or off to the side a little, perhaps half on top, with air space between any two pieces. That way the flames shoot up from the lower piece, catch an edge of the upper piece and start it burning.

Precept 3 has to do with types of wood:

LIGHT BURNS FAST; HEAVY BURNS SLOW. If a piece of wood is easy to lift, chances are it's soft wood, such as pine or cedar, and it's probably dry. These woods are great for getting a fire started, but they burn too quickly to provide much heat.

The heaviest woodsare either very hard or still damp, and should be used after the blaze has been roaring for half an hour or more. Once a fire is established with a good bed of glowing coals, practically anything will burn. That's when you want heavy wood, which burns slow and hot.

Put split wood on a still-growing fire. When it's roaring, switch to round wood.

Many people believe that a clean fireplace marks a respectable home. This is okay, but it doesn't help the firebuilder. We clean the hearth about once a month, and even then only halfheartedly. We find that an old bed of ashes helps raise the new coals, which provides more heat to keep the new fire going better.

Now a word about those silly fireplace tool sets they sell at department stores. We bought one last year with a useless, flimsy poker, a broom and a shovel, and I have yet to use any of them with satisfaction.

The tools needed for a good fire are only two: a solid, one-piece poker with no screwon gizmo to come loose when you need it most, and a pair of scissor tongs to pick up logs. If you want to sweep up, use a whisk broom and a dustpan. If you must have a bunch of shiny contraptions to make it look homey, buy them. But don't expect them to make a nice fire.

Last, once a fire is built, play with it. Every blaze likes a tender poke every half-hour or so, to bring separating logs close to one another. After a big winter dinner, that task may be the only thing left to keep you awake.