A special investigator for Senator Joseph R. McCarthy (R-Wis) spent two days in Cambridge attempting to get information on Arthur M. Schlesinger, Jr. '38, associate professor of History, the CRIMSON learned from reliable sources yesterday.

The investigator, who came from Washington to Cambridge October 5, was reportedly trying to get material for McCarthy's nation-wide radio-TV broadcast tonight. Whether McCarthy will attack Schlesinger, a top Stevenson aide, will not be certain until the broadcast at 9:30 p.m.

In giving what he describes as a carefully documented history of Governor Adlai Stevenson, "showing his connection with Communist causes and individuals who are known Communists," McCarthy has indicated that several of Stevenson's top aides would probably be mentioned.

McCarthy, when contacted over the weekend, refused to comment on Schlesinger. He did say, "I'm simply going to show all the links in the chain of Stevenson's history--his connection with communist causes--individuals who are known Communists.

"I'll show the extent to which he is a part of the Truman-Hiss-Achosen-Lattimore group.

"No Communist but . . ."

"I'm not calling him a Communist," McCarthy continued, "nor a pre-Communist. I just intend to give his history and let the public decide whether we want him to lead the fight against Communism."

The Wisconsin Senator said Stevenson's deposition on Alger Hiss during the first Hiss perjury trial would not be an important part of the broadcast.

The broadcast is scheduled for 9:30 p.m. tonight.