There are two explosive domes in this part of Washington -- one sitting atop Mount St. Helens, 70 miles away, and the other rising above the political cauldron of the state capitol.

Both domes have vented so regularly that the locals are not sure which aftershocks are more troublesome, nature's volcanic belches or man's embarrassing burps.

The latest man-made temblor came on Friday the 13th of last month, when Peter von Reichbauer, a slight and mostly obscure Democratic state senator who lives on a rural island in Puget Sound, showed up for work here with a bodyguard.

Von Reichbauer is not particularly superstitious but, in bringing the guard along, he was showing rare good judgment.

"I don't think the Democratic Party deserves to run the state of Washington," von Reichbauer announced on the fateful Friday. He then added that he intended to do what a lot of Democrats did in November: vote Republican.

Von Reichbauer's conversion, however, was more crucial than most. He held the pivotal vote in a state senate the Democrats held, 25 to 24, and his conversion turned over not only the senate but the entire state government to the Republicans for the first time in almost 30 years.

Life has not been the same in Olympia since, although some would argue that normal is only a state of mind in this constantly hell's-a-poppin' state capital.

Last year the majority leader of the senate and the cospeaker of the house were nabbed in an FBI sting operation. The two Democratic leaders were indicted for and convicted of conspiring with FBI undercover agents to help organized crime bring gambling into the state.

The quakes rolled on when the state's zany Democratic then-governor, Dixy Lee Ray, who had been informed of these shenanigans by the FBI, nevertheless offered one of the leaders an appointment to the U.S. Senate.

Toss in one of those now-routine lewd-behavior-in-a-public-restroom scandals, six eruptions by nearby Mount St. Helens, the case of the former Democratic senate chairman who returned from a banana-republic exile to sing about his old pals from the safety of a secret federal cell, 9,000 natural earthquakes from the unhappy volcano and, well, things were getting a little unsettling.

The citizenry of this normally idylic northwestern state may have thought all this would settle down after the election. They had given the governorship and the state house to the Republicans and had cut the decimated Democrats' hold on the senate to a single vote. Even their famous mountain seemed to be settling down to occasional mere rumbling.

Then, of course, came Friday the 13th and von Reichbauer's shockwave. "I think I have 24 new friends," the latest Republican said. Unfortunately, he also had made 24 new enemies, plus a few.

"Now I know why they say politics is the second oldest profession," thundered Sen. Ted Bottiger, who took over as the Democratic leader after the 1980 scandals but may have had the shortest reign as majority leader in Olympia's history.

"Cowardice!" cried the Democratic state chairman.

"Traitor!" shouted others. "Recall!" threatened his island-home Democrats, who started proceedings, but not until after they declared his seat vacant, a maneuver everyone ignored

Although the coup left the Democrats thunderstruck, von Reichbauer had been driving them to fits throughout most of the first five weeks of the legislative meeting.

In the Democratic caucus, where Bottiger tried to keep his slender majority intact, von Reichbauer demanded a special parking place for his car, closed-circuit television in his office, a higher salary for an aide than the law allowed. He got three key committee assignments, including the chairmanship of the Transportation Committee.

A few days before Friday the 13th a Democratic senator came out of one stormy caucus, and complained that von Reichbauer was acting like "a 12-year-old rich kid in the body of a 40-year-old man." Bottiger yielded on many of the requests, and finally rebelled when von Reichbauer asked for a state-financed mobile telephone in his automobile.

Shortly after that, the majority leader found he was leading a minority instead.

The Republicans just clucked. Long out of power, they nevertheless showed immediately that they knew how to exercise it under Oympia's dome. Their first act was to appoint a former zoo-keeper as the new Senate sergeant-at-arms.

"I'm used to working with both people and animals," announced the new doorman, Fred Hildebrand, who had watched over the monkeys at nearby Tacoma's zoo.

They next announced that more than half the Senate's Democratic staffers, some of whom had retreated recently from the Republican purge of the U.S. Senate to the presumed safety of Olympia, would get the ax.

But the Republicans graciously told the Democratic senators that they could hand out the pink slips. You've got the guillotine, the Democrats responded; you drop the blade.

The Republicans also had the keys to all the Senate's previously locked doors. They promptly responded by a daring midnight raid on the Senate printing office, where they grabbed several thousand letters accusing the GOP of being unkind the Democrats and other poor people.

Foul! the Democrats cried again. Mount St. Helens responded at just about the same moment by thumping the region with its strongest belch in months, an earthquake that registered 5.5 on the Richter scale and left the state's citizenry figuring that not much had changed after all.

More than two weeks later, the rumbles still have not settled down, and some beleaguered Democrats here were hoping they never would. With the GOP in total control, some long-stalled Republican bills -- raising of the state's 12 percent interest limit, lowering the timber tax as sought by corporate giants such as Weyerhaeuser -- seemed sure to be whisked into law.

Even worse for the Democrats, the Republicans had a lock on the legislature and the governor's chair in a year when redistricting could change the state's political map for years to come.

Not only will legislative districts be carved up, a job Democrats have handled rather bluntly in their own interests in the past, but the 1980 census gives Washington an extra congressman next year, a seat some say von Reichbauer wants, and the Republicans now have a chance to remake the congressional districts to their linking.

First, of course, they have to get around to such things. And since Friday the 13th no one in Olympia has had much time for legislating.

Last week the Democrats, with decades of experience in legislative ploys, kept the pot bubbling. Unable to do much more, they took a shot at censuring their errant islander, von Reichbauer.

Lt. Gov. John Cherberg, a Democrat who sits as president of the senate, ruled that a member couldn't vote on his own censure. That left the senate tied, 24 to 24. The president of the senate casts tie-breaking votes, and briefly it looked bad for von Reichbauer.

The Republicans hurriedly caucused. Then they came back with a ploy of their own, having learned a few things after watching from the outside for so long. They promptly targeted at random a Democrat senator, announced censure proceedings and said he couldn't vote. Then they targeted another one.

The Democrats fell back in disarray. It now looked as if everyone in the senate would be censured and no one would be left to vote. They talked all day, and then gave up on von Reichbauer.

"We have lost another day," groaned the former majority leader, Bottiger, it wasn't clear whether he figured that was a plus or a minus.

"We are all looking like asses," a Republican grumbled.

Over by the door of the Senate the new sergeant-at-arms smiled knowingly.