Observation of HadronicWDecays intt¯Events with the Collider Detector at Fermilab

We observe hadronic W decays in t{ovr t}{yields}W({yields}{ell}V)+{>=}4 jet events using a 109 pb{sup -1} data sample of p{ovr p}{sup -1} data sample of p{ovr p} collisions at sqrt[s] = 1.8 TeV collected with the Collider Detector at Fermilab. A peak in the dijet invariant mass distribution is obtained that is consistent with W decay and inconsistent with the background prediction by 3.3 {sigma}. From this peak we measure the W mass to be 77.2{+-}4.6(stat+syst) GeV/c{sup 2}. This result demonstrates the presence of a second W boson in t{ovr t} candidates in the W({yields}{ell}v)+{>=}4 jet channel.