The Capitol Hill Restoration Society House and Garden tour will open 10 houses on May 13, Mother's Day. Among them are the homes of Bob and Barbara Reich and Pat Singleman .

THE LAST time Bob and Barbara Reich had a party in their fancy old Victorian house, no one wanted to leave the master bathroom. "People came in the front hall, went upstairs to hang their coat, and never came down," said Barbara Reich."I finally went up to find out what had happened to everybody, and there they were, sitting on the marble steps of the tub, and the settee, talking and luxuriating. I'm going to plan to give my next party in the bathroom, with champagne cooling in the tub."

The bathroom is a party room. To begin with it's the size of most people's bedrooms and some people's living rooms. The focal point is the bathtub-a long skinny one encased in marble. It takes two steps to get into the tub, with one wide enough to sit on, in case you lose courage. It may be one of the few canopy tubs in existence-the fabric matching the rich Victorian patterned wallpaper and window curtains. On the walls are an assortment of old apothecary chests. The soft seat is the velvet-covered settee. The floor is covered in the thickest, plushest wall-to-wall carpet. The effect is decidedly opulent and not a little decadent.

The bedroom itself is large, embellished with a chaise lounge and a fire-place. Down a few steps and up a few more (why did the Victorians do it that way?) Is a working library. Behind is a utility room with washer and dryer. On the third floor are a guest room and an office.

Downstairs, there's plenty to see as well, if you can tear yourself away from the bathroom.

The chandelier that hangs in the Reich living room has led a nomadic life. It hangs expectantly, ready to shimmer at the next puff of air. Not much is known of its past, though the crosses on the larger crystals suggest a holy origin.

The Reichs found the chandelier in the Marche aux Puces , the flea market in Paris, on their honeymoon a few years ago. They have hung it in four houses in the last decade or so themselves-who knows how many churches or nunneries or houses it hung in before.

Changing houses is an occupational hazard for the Reichs. She's the owner of Barbara Held, Inc., one of the prime real estate agencies that developed Capitol Hill. He is a restorer, currently at work on the side galleries of their house. They paid $185,000 for this house, about six blocks from the Capitol on Independence Avenue SE. They figure they've put about $40,000 in the restoration, not counting Bob Reich's hard work in design and supervision as well as carpentry.

The house is in what is called the "Italianate" late Victorian style, perhaps the handsomest of the major Capitol Hill designs. Each tall, narrow window of the facade has an ornate eyebrow to accent it. Under the roof, woodwork detail is carefully outlined for emphasis. The Reichs use shutters in the lower half of each window. On the lower floor are stained glass rectangles, hung like paintings in the upper windows. Upstairs are white curtains with the traditional ball fringe.

The original handsome wood doors were not what you'd call weathertight when the Reichs bought the house-it cost them close to $400 to rebuild them. "And you can still see daylight through them," Reich said.

The Reichs bought the house about a year and half ago. It's their third Capitol Hill house, with a digression to Georgetown for a few years along the way.

"This house was built in 1871 by a Michael McCormick," Reich said. "We bought it from the estate of a retired general, who had lived here for years.

The Reichs had to upgrade the wiring and plumbing, as might be expected. The house had kept its original ornate ceiling medallions , cove molding, carved Italian black marble fireplaces and chaste ribbed woodwork. The Reichs were delighted to keep all of these embellishments. As have many other people, the Reichs have turned more and more traditional over the last four houses, choosing to restore rather than remodel. (Their first Capitol Hill house was much less staid-with a fish pond in the living room and a fountain that sprayed up two stories to hit a skylight.)

Their current parlor is not prim, but very proper to the period. Coming in from the side hall, you see double rooms in shades of brown with one wall of Victorian geometric paper. The rooms have matching fireplaces in the Victorian manner. A velvet covered mahogany sofa sits against the front wall.

"Victorian houses have one problem," said Barbara Reich. "There's no wallspace, with all these windows and double doors." So the furniture mostly floats in the room. Almost everything came from their Georgetown house, and fits as though it belonged-not surprising, since that too was Victorian.

In the back parlor is an elaborately inlaid library table, with a literary history. Humorist Booth Tarkington bought it in 1920 and gave it to novelist Kenneth Roberts in 1933. Above the mantlepiece is a portrait of Mrs. Reich's late father, a Lutheran minister.

(It's a good thing the Reichs have a double parlor. She's given dozens of parties here recently to benefit Friendship House. Today is Friendship House's annual Market Day, selling handmade crafts from furniture to clocks.)

As it is customary for houses of this design, the dining room sits behind the parlors, jogging a bit to allow for a double gallery. There's a fireplace here as well. Instead of curtains, the Reichs have shelves holding their glass and china collection. The kitchen is behind.

The garden and fishpond and the carriage house (which will no doubt be rented to pay the mortage) are still under construction by Bob Reich and his team.

Pat Singleman's rented apartment on 11th Street NE is a totally different sort of Capitol Hill home. You walk in the door, and if you're not careful, you'd fall down eight feet or so into the coversation pit.

Singleman's apartment is tiny, but certainly dramatic. The first floor is cut away to make a light well and stairway down to the living room. The kitchen is on a balcony level, some steps up from the mid-way entrance. The bedroom and bath are also on the middle level.

Singleman has furnished the apartment in a contemporary style with grey velvet upholstery and mirrored vertical blinds, paintings by Bill Fraser and Agnes Anilian.

When she came from New York to work for the Senate Judiciary Committee's subcommittee on administrative practices, Singleman set out to look for an apartment. This one was right around the corner from a friend's house where she was staying. "After I saw this apartment, I couldn't forget it, even though it looked even smaller empty."

Singleman pays $140 a month for the apartment.

According to research by the tour committee, a grocery store was built on the site in 1884-for an estimated cost of $2,000 for a man named John Mansfield. The building was remodeled in 1890 to add a dwelling over the store for Fritz Yeider. Not so long ago the structure was remodeled into two contemporary apartments.

The 22nd annual Capitol Hill House and Garden Tour also includes the homes of Robert Cooneys; Michael Tubbs and James F. Burke; the Robert Herrema family; the Jack Chases; B. David McDowell and Alan Keffer; Victor Kamber; David Deal and Douglas Mulligan; and Philip A. Ridgely.

Tickets for $9 each are on sale at Eastern Market Saturday. Tickets on tour day are $10. Only 1,500 will be sold. A jitney will run during the 1 to 6 p.m. tour from Eastern Market with refreshments from 3:30 p.m. to 6:30 p.m. at St. Peter's Rectory. Anyone who wears high-heeled shoes will have to take them off at the front door. CAPTION: Picture 1, The master bathroom in Bob and Barbara Reich's house; by Margaret Thomas-The Washington Post; Picture 2, Pat Singleman in her living room, by Margaret Thomas-The Washington Post