CAMBRIDGE Mass (AP) -Investigators searched today for the weapon used to kill Jane Britton 22 a Harvard graduate student whose’ body-was found sprawled face down across a blood-spattered 'mattress in her apartmenj A medical examiner said the daughter of the administrative vice-president of Radcliffe College had been struck a massive : blow on the left side ofthe head behind the ear by Ae weapon Investigators theorized a hatch et or a cleaver was used Police said toddy they were searching for a hammer that the girl used in her archaeology studies but was not found in her apartment Police also questioned girls in the area’ who have complained ' about prowlers in the hope that those who have seen someone might provide leads! Dr Arthur McGovern of Cam-bridge who ruled the death a homicide said the shape of the wound indicated that the girl was facing her assailant when struck He said she had been dead-19 to 12 hours when her body dad' - in a -'disarrayed nightgown was found at 12:49 p m Tuesday An autopsy performed Tuesday night by McGovern- disclosed that the girl had 'also been struck at least (vice in the face with the weapon Authoritiessaid the autopsy ' revealed no evidence of-sexual ' attack" Wics said they were without area--"a suspect They said there was no Evidence of a struggle or of robbery The slim petite brunette was the daughter of Mr and Mrs J Boyd Britton of Needham A In Jane Britton graduate of Radcliffe she was In her second year as a student to anthropology - - Miss Britton farilcn to appear in a class Tuesday morning p lice said The body was found James H Humphries J7 a ’ ‘ anthropology student they After Nad By: G JL BURNHAM The Holyoke ' National Bank has decided to raise Us prime rate to 7 per cent to the wake ’ of yesterday’s announcement by the First National City Bank of New York that it was increasing its prime rate in a move described as a steady boy friend end fay Mr and Mrs Don Mitch-' ell the girl's fourth-floor neigh- - - tons to the apartment house near ' Harvard University ' Detective Loo Davenport heed - of an 18-man investigating team S'eced together this account of e events of the previous night: Humphries and Min Bntton went out to dinner Monday -night then went - skating on Cambridge Commqn ‘returning to her fourth floor apartment at - about 16:30 pnu Humphries left ' at about 11:45 p!m and the girl ' went across the hall and Tinted for ‘a while -with the Mitchells She seeiqpd cheerful discussed in exam she had coming up - then retired to her own apart-ment at-abou 13:30 am The girl failed to' appear to -class Tuesday and Humphries' came toihe apartment house ihortJjKifter noon after which behind the Mitchells made the SiMvery " The apartment is on the other Please Turn To Page t City Boost that caught the Federal Beserva Board by surprise and precipitated a nvi of rate increases to most of the nation’s major banking firms - - L-s 1 v ' ' ‘The primrf rote fa the interest which commercial banks charge their largest and most creditworthy customers end an in--crease fa usually reflected to