It was by far the most spontaneous debate thus far this year. For three hours last Thursday afternoon, the assembled members of the Maryland House of Delegates took up the sensitive subject of their salaries.

Now the prospect of a debate on this particular topic, you must understand, is not enticing to most politicians. In fact, there are few things in this world that they seem less anxious to talk about. Warts, maybe. Or the price of pomegranates in Pago Pago.

As a general rule, however, most legislators do everything that they can to avoid the subject of their own salaries.

But a funny thing happens to this natural reticence when legislators are forced to talk about their salaries - and not only forced to talk about them, but forced to vote on them as well.

After all, the delegates would hardly be human if they didn't feel good about getting some sort of pay increase. But they are also politicians, and few moves as politically self-destructive as voting yourself a raise. Especially in an election year.

Confronted with this situation last week, the members of Maryland's House of Delegates reacted in a variety of ways. And, since there were 11 salary resolutions they could choose from, some members also reacted with a contradictory variety of votes.

The logistics of the situation went as follows. Over the summer, the General Assembly Salary Compensation Commission proposed a sliding scale of salary increases to cover the years through 1982. According to this scale, legislators, who are now paid $12,500 annually for their work, would receive $16,000 in 1979, $16,750 in 1980, $17,600 in 1981 and $18,500 in 1982.

In addition, the current expense allowance of $35 per day, which is paid to any senator or delegate who shows up for at least one floor vote or one committee vote, would be increased to $50 per day.

This seemed a little high for some delegates, so a number of other salary proposals were advanced after the compensation commission report was made public.

These included three separate proposals to keep salaries at about the $12,500 level for the next four years, proposals to raise the salaries to $15,000 - or in one case $16,000 - over the next four years, and alternative sliding scales that didn't go quite as high as the proposed commissions salaries.

Add to all this the key, overriding fact: If none of the resolutions passed, the commission's recommendations would automatically go into effect. Which is what eventually happened.

The fact that there was a multitude of proposals to choose from - and the fact that the delegates could make their choice by deciding not to choose anything - gave everybody present a fair degree of latitude to dance around when casting their votes on the question. And some of them did some fairly peculiar dances.

Take Del. Hugh Burgess, for instance. The Howard County Democrat did the most courageous thing possible on the very first vote taken. He voted with the 64 other delegates who favored a resolution identical to the salary commission report.In that way, he put himself in the politically unpleasant position of having voted in favor of the highest pay raise.

"I'm bull-headed," Burgess said a few days ago. "I'd rather we voted for the full increase than do what we did and back into it." He then echoed arguments that had been made on the floor - that the job of being a legislator takes up far more time than the three months a year it is supposed to take, that self-employed delegates have trouble keeping up with their other work - in short, that the legislators deserve the money.

After putting himself out on a limb with the other 64 delegates, however, Burgess turned around and voted for the three proposals that would leave the legislators' salaries just about where they are. These votes, he said recently, were made out of resentment at what he saw as his colleagues' decision to fudge on the tough, first vote.

"At that point I was just mad at the way everybody repudiated (the commission report)," he said. "I felt if they didn't have the strength of their convictions to vote for a raise, they shouldn't get one."

Whatever his motivation, however, Burgess went down on paper casting almost completely contradictary votes. And he was not alone. Del. Mildred Harkness (D-Prince George's) also voted for four different proposals.

Like Burgess, Harkness was among the 65 delegates who admitted, on the record, that they wanted the full commissions increase. Then in the subsequent votes, she favored the flat $15,000 salary over the next four years, as well as two of the proposals that would have left delegates with the $12,500 salary they have now.

"I didn't know exactly what would be fair," Harkness said this week. "Coming from the position of a city councilman, making $1,200 a year, they all looked good to me . . . I was looking for anything that would be acceptable. I tried the highest. I tried the lowest. I tried the middle. None of them worked out.

"I wanted to find what was acceptable, because I felt we should have to make a decision about it."

At least six other delegates cast a contradictory series of votes during the chaotic three-hour session, but one delegate, Prince George's Democrat Gerard Devlin, claims the record for consistency. "I voted against 90 percent of the salary raise proposals," he said after the vote, with his tongue firmly in his cheek.

The only one he voted for was the highest raise.