By HILDA INCLAN

Metro bomb expert Tom Brodie finished identifying today the charred and torn objects found in the wreckage of a Little Havana home rocked by a blast last March 20.

Brodie was a key witness against Humberto Lopez Jr.' and Luis Crespo, two Cubans found inside the garage and injured by the explosion of a booby-trapped book which police said they were making.

A third defendant, Joaquin Miranda, was discharged yesterday by Circuit Court Judge Arden Siegendorf on insufficient evidence in response to a plea by his lawyer, Lawrence Faye.

Miranda was seen at the site of the explosion but was uninjured. Witnesses failed to establish he had been on the scene before the blast.

All were charged with possession of explosives with intent to injure and without a permit.

Supporters of the defendants, representing various exile organizations, were in the courtroom yesterday.

Miami Mayor Maurice Ferre sent a letter of character reference to the judge on behalf of Lopez and Crespo. He later explained he had done so as a person and not as Mayor, and out of concern for the men's welfare and not to condone any criminal offense.

He sent his assistant Luis Laaredo to the Justice Building to try to set up a phone conversation between himself and the two defendants, but they had to go back into the courtroom before this could be done.

Brodie identified the charred top of a workbench where the bomb allegedly blew up, over objections from defense attorney Melvyn Greenspahn. The bench top had a hole in the center.

Assistant State Attorney James Woodard asked him to explain the explosive device the suspects were allegedly making.

He offered as a state exhibit a sample of a hollowed-out book Brodie had booby-trapped, with clay simulating C-4 plastic explosive connected to a small radio battery and mouse trap. It would blow up when not held tightly shut, if the explosive were real, Woodard said.

The jury of three men and three women was visibly startled when he took his hand off the cover allowing the book to snap open. It went "click."