A one-alarm fire at 56 Mt. Auburn St. shattered the dull torpor of reading period last night. The fire, which a second deputy chief of the Cambridge Fire department described as "a tremendous amount of fire," burned out most of the inside of the dilapidated condemned wooden structure.

The flame burst out suddenly at 8:30 p.m. By 8:48, a Cambridge policeman said it was "pretty well under control."

Three large hook-and-ladders wererequired to put out the blaze. Only one general alarm in Cambridge fire stations was sounded.

Don't Do it

Firemen who had entered the three-story building while it was still aflame said that no one was inside the building. No fireman suffered any injury in extinguishing the fire, although one, suited in asbestos, entered the burning building to cries of "Don't do it!" Applause greeted his reemergence.

Inside the building, owned by the Wasserman Corp., no floors remained on the second and third stories. Firemen attributed this to the fire, although one Cambridge policeman said that the building was in the process of demolition and this could have accounted for the absence of the floors.

Cambridge Deputy Fire Chief John Healy said that he had "no idea at all how the fire started. By the time we got here the fire was in full blast and we just wanted to put it out. As in any case where we don't know how a fire started, we'll turn it over to the State Fire Marshals."

Healy called the entire affair "no more than a big bonfire." The fire had been called in at 8:30 p.m. by some young person, he added.

A large crowd of people watched the fire. They applauded and cheered until 9:05 p.m. when the last visible flames were put out.