THE Chief Justice, Mr Justice Liam Hamilton will next week preside over the largest Supreme Court since the foundation of the State. In the biggest structural change in 60 years the court will sit For the first time in two divisions in newly created chambers.

The bicameral sittings will also shepherd in the greatest ever single personnel change in the composition of the court.

The original Free State Supreme Court in 1924 comprised three judges. This grew to five with the enactment of de Valera's Constitution in 1937. That number will rise to eight, four of them appointed in the last four months, to enable the Supreme Court to sit in two divisions on Tuesday.

The Chief Justice will sit with four of his colleagues in the first division, the constitutional court of five; three judges will hear criminal and other cases in the new division.

Notwithstanding the setting up of the new three judge chamber next week, it will be six months at least before the two divisions of the court are in permanent session.

One of the new appointments to the court, Mr Justice Kevin Lynch, is hearing the long running Bula case, and will sit it out to its conclusion. His place will be occupied on Tuesday by the President of the High Court, Mr Justice Declan Costello, an exofficio member of the Supreme Court.

Legal observers expect that it will be a year or more before the current backlog of cases before the court can be reduced to manageable proportions. The reorganised Supreme Court is not likely, therefore, to take over jurisdiction for criminal appeals before July 1997.

As a court in transition with a huge intake of new blood, the biggest Supreme Court in the history of the State is difficult, if not impossible, to characterise. But one pivotal question is already being raised by legal practitioners.

Given that the Supreme Court has been thrust into the centre of the political life of this State in recent times on public issues such as abortion and divorce, which of the eight judges will sit in the court hearing constitutional matters?

Under the Court and Court Officers Act 1995, the Chief Justice has been granted the same power as the President of the High Court to select which judges will hear which cases. Already, however, Mr Justice Hamilton has established a rule that judges will sit on the five member constitutional court on the basis of seniority alone.

This means, in effect, that the original five judges, since they have the greatest length of service in the Supreme Court, will comprise the court on constitutional matters in normal circumstances.

The immediate move to immunise the newly extended Supreme Court from any possible criticism about its composition in high profile cases is a good illustration of the importance which the Chief Justice attaches to the role of the court vis a vis the other institutions of State.

Mr Justice Hamilton is regarded by colleagues as the quintessential pragmatist. He knows the wider political world in which the court operates.

Having chaired the beef tribunal, the longest running and most politically divisive investigation ever held, he was appointed Chief Justice in the autumn of 1994. In less than two years he has ushered in more structural change in the Supreme Court than any previous chief justice.

He is credited, for example, with persuading the Minister for Justice to change his mind on the proposal in the original Court and Court Officers Bill to establish a separate court of appeal.

He presides over the Judicial Appointments Board. Aged 68, he has four years to run before retirement.

The longest serving judge in the current court is Mr Justice Hugh O'Flaherty. He replaced Mr Justice Brian Walsh in 1990. He is also, at 58, the second youngest member.

Like the Chief Justice, he is a pragmatist who can write a good judgment. Before the recent influx of new talent, he had often been tipped as the next chief justice.

He is regarded by some legal observers as a conservative. Much attention will focus on his judgment on Mr Des Hanafin's challenge to the validity of the result of the divorce referendum.

Mr Justice John Blayney (70), appointed to the Supreme Court in October 1992, is its oldest member. He was an outstanding trial judge in the High Court for many years.

His performance, according to observers, has been a bit more mixed in the Supreme Court. He, too, is regarded as conservative on social issues.

It is public knowledge that he acted as legal adviser to the original Pro Life Campaign in the early 1980s.

Mrs Justice Susan Denham (51) is not only the first woman member of the Supreme Court in its history but the youngest member of the current court. Her nomination in December 1992 restored the long standing tradition of appointing a Protestant to the court.

There is some substance in comparisons of her with the President, Mrs Robinson, since she is consistently liberal in her judgments. Her common sense is acknowledged by legal experts.

She is likely to remain the only woman in the Supreme Court for some time because of the dearth of experienced woman judges, with the exception of Miss Justice Mella Carroll, in the judicial ranks immediately beneath her.

The fifth member of the court of five, in terms of seniority, is Mr Justice Donal Barrington. Aged 68, he was appointed last January.

He was the Tanaiste's first choice to be President of the High Court during the political crisis in late 1994. But his lack of 12 years' continuous experience - because of his absence to serve as Judge of First Instance in the EU - barred him from consideration for the post.

That technical problem has since been rectified in the Court and Court Officers Act.

An excellent judge in the High Court he has, so far, delivered nothing of substance in his four months in the Supreme Court. Legal observers see him, however, as the potential wild card in the court.

Flouting the conventional wisdom of the political and legal establishment in late 1986, he granted the injunction to the late Raymond Crotty restraining the ratification of the Single European Act.

He is known as someone who can be persuaded only by legal argument.

The three new judges appointed to the expanded Supreme Court six weeks ago bring a potential breadth of vision to its deliberations.

Mr Justice Ronan Keane (64) is a profound thinker who, most observers agree, should have been promoted years ago. He is an expert on planning, local government and commercial law.

Mr Justice Kevin Lynch (68) is regarded as a solid all rounder. The son of Judge Fionan Lynch, a former Minister and Ceann Comhairle, he felt the full glare of publicity in the Kerry Babies case.

Mr Justice Frank Murphy (64) is the insolvency expert in the court, having handled most of those cases in the High Court for the past five years.

The Supreme Court is passing through a period of unprecedented change, and further changes in the pipeline.

The working group on a courts commission, chaired by Mrs Justice Denham, is expected to issue an interim report later this year on the financing of the courts system, and on the relationship between the courts, the Department of Justice and the Oireachtas, among other matters.