In a flight of senatorial rhetoric, Sen. Frank Church (D-Idaho) has likened the treaty under consideration -- SALT II -- to the Treaty of Versailles, but the scene in the paneled Senate hearing room hardly confirms the grandeur of Church's comparison.

There has been little drama in the Foreign Relations Committee's formal "markup" of the strategic arms pact. Some vociferous senatorial posturing, yes, and a few sharp words, but the general atmosphere during five days of hearings last week has been flat, often dreary, usually boring. This may be a great event, but even great events must fit into conventional proceedings.

In fact, the outcome of the committee's work will be significant. The treaty seems assured of approval by at least eight of the 15 members, but if it gets no more than eight or nine votes its chances on the floor are poor. Eleven "ayes" on Foreign Relations would be a reasonably good omen for SALT, though not conclusive.

The process of a markup is largely mechanical. The committee is working through the treaty article by article, discussing the import of each, often raising potential loopholes or ambiguities, and considering possible amendments to the treaty or reservations that might clarify or change it.

An amendment to the treaty itself would require reopening negotiations with the Soviet Union, an outcome the Carter administration fervently hopes to avoid. The Senate can also add reservations or "understandings" to its resolution of ratification. The president would have to incorporate these into the formal American "instrument of ratification" that the Soviets would have to accept before the treaty could come into effect. There can also be lesser understandings that simply spell out an American interpretation of one or another provision and which the Soviets would not have to accept formally.

Joseph R. Biden Jr. (D-Del.) may be having more fun in the great SALT debate than any other senator. Just 36, just beginning his second term in the Senate, Biden is a clever and ambitious politician, one who talks to his friends about running for president one day. The Foreign Relations Committee's SALT hearings have brought more attention to Biden than anything he has done previously as a senator.

What has drawn attention to him has been Biden's eagerness to do battle with the only active presidential candidate on the committee, Howard H. Baker Jr. (R-Tenn.). Baker has taken the position that SALT II must be radically altered by amendment or he will not support it.

In July, Baker went after administration witnesses at the initial SALT hearings, trying to dramatize weaknesses in the treaty. Biden -- whose turn to question witnesses before the committee usually comes right after Baker's -- in turn went after the minority leader, challenging his criticisms. bDespite a tendency toward long-windedness, Biden seemed to get the best of these exchanges. After a few days Baker stopped coming regularly to the hearings.

This week Baker has begun offering amendments to the treaty, and Biden is again disputing him. At one point Baker challenged his colleagues to have the courage to change the treaty even if it upsets the Soviet Union: "I, for one, am not put off by the thought that what we do here has to be submitted to the Russians . . . If we start out by saying that we are not going to change anything because we are afraid it will upset the Russians, we are never going to do any good with this treaty."

Biden had an answer for this line of argument:

"There is no reluctance on my part . . . to tell the Russians that they must agree to certain things. The distinction that I would like to make in light of the characterization the senator from Tennessee just made is that we only should do that when it serves our national interest . . . This [Baker proposal under consideration] does not serve our national interest."

At the press table, where the Baker-Biden show is now anticipated as good theater, reporters smiled.

One newspaper account of the first week's markup sessions quoted anonymous Carter administration sources who criticized Chairman Church for failing to control the meandering hearings. This angered some on the committee who felt it was the administration whose act left something to be desired.

Lloyd N. Cutler, the Washington lawyer who recently signed on as counsel to President Carter, is the chief administration spokesman in the hearings. It falls to him to reiterate the arguments initially made in July for the treaty's provisions. Cutler is a lawyer, not a politician, and his inclination is to jump right past political rhetoric to get to the heart of a matter.

When Baker proposed an amendment that would significantly alter the treaty by forcing the Soviets to count their medium-to-long-range Backfire bomber under the limits of SALT II, Cutler did not recall any of the admiistration's arguments about why Backfire had been left out of the treaty. Instead he jumped to the immediate problem that he thought approving Baker's amendment would create: it would reopen negotiations with the Russians, he noted, and he proposed to explain in a secret session why this would be bad.

Several senators, particularly Charles Percy (R-Ill.), Church and Biden, were taken aback. Why a secret session? Why don't you make the arguments about Backfire? Percy and Biden actually made some of them for Cutler. Then Cutler had a chance to explain in a closed-door session what the United States expected the Soviets to demand in return if the Senate required the counting of Backfire.

By the end of the week Cutler seemed more comfortable with the rhetorical posturing that comes naturally to members of the Senate. He joined right in. p

A confidential poll of senators would probably reveal a widespread feeling that one of the most eager rhetorical posturers in that body is Sen. Richard Stone (D-Fla.). Stone's colleagues do not find him especially popular or effective, but he is an accomplished performer. In the SALT hearings, he has returned repeatedly to issues connected with Cuba, whose former citizens make up a large part of his constituency.

This week the issue that animated Stone was Soviet G-class submarines, old and noisy diesel-powered subs that were excluded from SALT I and now again from SALT II. The Soviets station them in the Baltic and Pacific, according to the Pentagon. These subs "are cruising our waters," Stone declared dramatically.

Weren't they last seen near the United States (in Cuba) in 1974, an administration official asked Stone. "Nineteen-seventy-four is not now," the official added.

"Now that is a little bit cute," Stone replied sarcastically, "I am not saying that they are offshore today. I am saying that their range is such and their mission is such that they can and they have done that."

Other senators noted that it would violate Soviet-American agreements about Cuba to base the G-class subs in Cuba in the future, but Stone was not convinced.

On the Foreign Relations Committee, Stone, John Glenn (D-Ohio) and Edward Zorinsky (D-Neb.) will cast the votes of greatest concern to the White House. Without the support of all three, SALT's prospects will be endangered.

The markup continues Monday. Final action seems possible next week, but more likely a week or two later.