World Notes

LIBERIA Comrades Turned Enemies

For the better part of a day last week, no one knew who was in control of Liberia (pop. 2 million), the African nation founded in 1847 by freed American slaves. Diplomats in Monrovia reported that rebels had attacked the Executive Mansion at dawn Tuesday, using artillery and heavy machine guns in a full-scale battle with government troops. Soon after the fighting began, former Army Commander General Thomas Quiwonkpa announced on the radio that he had overthrown President Samuel K. Doe, 33, whom he accused of corruption and brutality. That evening, however, Doe assured his countrymen that the coup attempt had failed, although Quiwonkpa was still at large.

Five years ago, Quiwonkpa helped Doe seize power in a bloody coup against President William Tolbert. But the young President distrusted his former comrade and dismissed him from his army post. Last month presidential elections were held; despite widespread reports of voting fraud, Doe imperiously declared himself the winner. At week's end the President announced that Quiwonkpa had been spotted near the radio station and shot dead. Quiwonkpa's bullet-riddled body was displayed at the army barracks where he once had an office. NICARAGUA Beyond the Diplomatic Pale

There was a time when a job at the U.S. embassy in Managua was the envy of many Nicaraguans. The 200-odd nationals employed by the U.S. as guards, drivers, administrators and accountants earn at least twice as much as most of their countrymen. Last week those jobs suddenly seemed less appealing. Since Nov. 2, the leftist Sandinista government has summoned at least 17 embassy employees for interrogation at a nearby security compound. Some reported afterward that they were forcibly detained for up to 13 hours by security agents who subjected them to abusive and threatening treatment.

The detainees complained that they were shunted from location to location with their eyes closed and their head between their legs, then put in small, dark cells. The Sandinistas' harsh questions reportedly delved into the detainees' private lives and the internal workings of the U.S. embassy. All were accused of being CIA plants and of being "counterrevolutionaries" because they worked for the U.S. Washington responded by lodging a sharp diplomatic protest. The Sandinistas promptly issued a statement declaring that the interrogations were "strictly internal" and therefore "outside the sphere of diplomatic relations." SOUTH AFRICA Banning Through the Back Door

Nearly 7,000 people have been detained by South African security forces this year. More than half have been freed, but at least five antiapartheid activists released last week found that the efforts to silence them did not end with detention. The group includes four whites and an Indian member of the executive board of the multiracial United Democratic Front. By the terms of their release, they have been effectively barred from leaving Johannesburg and from political activities. The Detainees' Parents Committee, which monitors detentions, denounced the curbs as "banning through the back door." Seven other former detainees appealed to the Supreme Court in Pretoria last week for an order that would prevent police brutality against prisoners held under emergency regulations in force since last July. The seven claim they were beaten, hooded with plastic bags, dunked in buckets of water containing tear gas and tortured with electric shocks. The case was dismissed on a technicality. Meanwhile, some 200 to 300 detainees being held at prisons in the Cape Town area reportedly began a hunger strike to protest their confinement. VIET NAM A Bid to Break an Impasse

Since the last U.S. ground troops withdrew from Viet Nam in 1973, relations between the two countries have been frozen, in part over Hanoi's failure to cooperate with the U.S. in accounting for 1,787 American G.I.s listed as missing in action. In a bid to break the diplomatic impasse, the government of Premier Pham Van Dong last summer promised to resolve the MIA dispute within two years. Hanoi offered to identify and turn over to the U.S. the remains of any American soldiers it found. Washington insisted on direct participation in any Vietnamese search.

In a concession to U.S. negotiators, Viet Nam agreed in principle last month to joint MIA recovery operations, scheduled to begin this week at the site of a 1972 B-52 crash near Hanoi. There is good reason for Viet Nam's newly cooperative mood. Its annual per-capita income is roughly $125, and the $2 billion a year it receives in assistance from Moscow is not likely to increase. Viet Nam is said to want the MIA problem solved as a first step toward restoring official relations with the U.S. and establishing economic ties. Washington insists that it will not consider sending an ambassador to Hanoi until Viet Nam withdraws its troops from Cambodia. BRITAIN Time to Go off the Clock

For centuries the British have set their clocks by the Royal Greenwich Observatory's world-famous chronometers. The U.S. persuaded the nations of the world to agree in 1884 that the location of the observatory, then on the Thames at Greenwich, should be the site of the imaginary north-south line that marks 0DEG longitude. Only the French objected, unsuccessfully proposing a navigational line going through the center of Paris. Since then Greenwich mean time and the Greenwich meridian have become universally accepted as the foundation of worldwide timekeeping and navigation.

This month the observatory announced that Britain is going off the clock. The problem is cost. Since the 1960s, GMT has been measured by six atomic clocks, accurate to a billionth of a second. Starting next year, the clocks' vacuum tubes, which cost almost $30,000 each, will not be replaced when they wear out. The observatory plans to put the money instead into astronomical research. GMT will have finally been superseded by Coordinated Universal Time, a 13-year-old international standard kept by 150 atomic clocks around the world. Universal Time is maintained by the International Time Bureau, which is based, perhaps fittingly, in Paris.