Tension mounted in the Maryland House of Correction at Jessup yesterday as prison guards, reacting to the escape of 30 inmates on Wednesday night, conducted a shakedown of dormitories and cellblocks. They uncovered crude knives, chains, syringes and iron bars hidden by prisoners.

Prison guards, already frustrated by staff shortages that they believe led to the breakout, said there had been "incidents" between guards and inmates during the day, "It's not a whole lot of fun in there," said one officer. "Yeah, we're all scared."

Maryland Gov. Harry Hughes yesterday ordered the hiring of 46 new guards for state prisons, 13 of whom go to the Jessup complex, where a single man stood guard over the dormitory where inmates cut through a bar and wire-mesh screen to escape.

But Hughes agreed with corrections officials that it would be difficult to improve the "outmoded and antiquated" facilities that enabled the prisoners to make good their escape from the century-old, medium-security institution.

Late yesterday, eight of the 30 inmates who escaped were still at large.

The fugitives include men convicted of armed robbery, assault and conspiracy to commit murder. Police said six of the men came to prison from Baltimore, one from Seat Pleasant and one from Dunkirk in Calvert County.

After a day of long and largely fruitless patrols through a 66-square-mile area around the prison, state police last night called off further dog-tracking details and reduced their extra complement of officers to five.

Two inmates were arrested yesterday morning trying to hitchhike at the junction of the Baltimore-Washington Parkway and Rte. 197 in Laurel.

One, Michael Pollack, who had been convicted of first-degree murder, was picked up shortly after 1 a.m.

The other, Glenn Grace, who was found at the same spot at 9:30, was serving time for robbery and assault.

"The guy was really ready to come home," said state police Sgt. Benjamin Cohey, who picked up Grace. "He was wet, his clothes were tattered. He was completely straight-faced. The first thing he did was drink about a gallon of water."

All of those captured were being retured to isolation cells at the Jessup prison, officials said. After interrogations, they were moved to high-security cellblocks, where they will be held until the escape charges against them are resolved. Disciplinary hearings by corrections officers will begin on Monday.

John R. Byrne, the assistant warden in charge of security at the House of Correction, said that interviews with the escapees and the search of the prison had not produced new evidence about the escape. "It's likely we won't ever find everything out," Byrne said. "If tradition holds true, the inmates won't tell us anything."

Despite prisoners' angry responses to the shakedown -- the first comprehensive search at the prison in 20 months -- Byrne said the gaurds, though tense, acted with restraint.

There were reports of shouting matches, jeering and generally tense encounters as the guards entered cells in pairs to conduct their search, but no violence was reported.

"The guards are aware that there are meetings going on with the governor," Byrne said, "and they're waiting to see what the outcome is."

Hughes met with state Public Safety and Correctional Services director Gordon Kamka and Corrections Commissioner Edwin R. Goodlander yesterday morning to discuss "the entire correctional system and its needs."

Later, Hughes issued a statement announcing his order that 46 guard vacancies would be filled immeidately because of "shortages in many staff areas . . . underscored by the recent incident."

State officials said later that the cost of the new hirings would be about $500,000 annually and might force Hughes to ask the legislature for a supplemental appropriation to cover part of the new salaries.

Officials said the Corrections Department's 1981 budget request for additional staff -- originally denied -- might now be reconsidered. Hughes said studies showed that there was an overall shortage of 103 positions in the corrections facilities, which currently employ more than 3,000 persons.

Goodlander said that his department would ask the legislature next year to authorize the renovation or reconstruction of the House of Correction. He added that state studies had shown that renovation of the complex might not be worth the price.

The House of Correction has been overcrowded for years, and even six years ago was condemned by an Anne Arundel County grand jury as a "barbaric" prison with "only one practical use, that of a movie set for James Cagney movies."

The state is now under a court order to reduce the population at the prison from 1,494 to 1,274 by July 1980. But Byrne said in an interview yesterday that the complex has problems that no staffing increase or population decrease can solve.

"The problem is the total facility," Byrne said. "It was built for different times -- when prisoners were chained up in little cells -- and there were expansions built on it at various times with no shape or reason."

Dormitories were arbitrarily attached onto other parts of the prison at angles as the complex expanded, Byrne said, creating "corners and holes" that made security difficult and efficient movement of prisoners nearly impossible.

An official at the prison said one of two electrically operated doors giving access to the dormitory where the escape occurred had been broken for some time. He said the broken door would make it more difficult for the single guard on duty to monitor the dormitory.

Byrne said that recently court-ordered reductions in the number of inmates in the state's maximum security prison in Baltimore had forced Jessup to accept many more violent men, even though it is designed as a medium-security facility.

The result, Byrne said, had been a rash of incidents of bar-cutting and other escape attempts in the first six months of this year. Prison officials have discovered more than 20 instances of cut bars alone, Byrne said. It was a single cut bar in a dayroom window that led to Wednesday night's mass escape.

"We could insure there were no escapes," Byrne said. "We could lock these men up and chain them like animals, and nobody would get out. But we have to have a trade-off. In the long run, it's more constructive to try and have more flexible routines -- to have activities and programs that the men can participate in -- than to worry only about stopping escapes."