▁P aste ur ▁Institute ▁to ▁meet ▁with ▁Gast on ▁Ram on , ▁who ▁had ▁recently ▁discovered ▁that ▁tre ating ▁a ▁pot ent ▁di ph ther ia ▁to x in ▁with ▁formal de hy de ▁and ▁heat ▁could ▁make ▁it ▁non - to xic ▁( result ing ▁in ▁a ▁to x oid ), ▁making ▁it ▁safe ▁for ▁v acc ination . ▁Since ▁Ram on ▁could ▁only ▁test ▁the ▁effect iveness ▁of ▁the ▁to x oid ▁on ▁a ▁small ▁scale ▁in ▁his ▁lab , ▁Fitz G er ald ▁c abled ▁Ram on ' s ▁methods ▁to ▁Peter ▁Mol oney ▁and ▁requested ▁that ▁he ▁" drop ▁everything ▁and ▁immediately ▁begin ▁prepar ing ▁and ▁impro ving ▁the ▁to x oid ". ▁In ▁ 1 9 2 5 , ▁Ed ith ▁M . ▁Taylor ▁joined ▁Con n aught ▁Labor ator ies ▁and ▁contributed ▁imm ens ely ▁to ▁impro ving ▁the ▁cult uring ▁process . ▁ ▁Tri als ▁in ▁Toronto ▁soon ▁proved ▁to ▁be ▁a ▁success , ▁demonstr ating ▁imm unity ▁in ▁staff ▁members ▁given ▁the ▁to x oid . ▁Field ▁tri als ▁were ▁soon ▁launched , ▁beginning ▁in ▁W inds or , ▁Ontario . ▁Between ▁September ▁ 1 9 2 5 ▁and ▁February ▁ 1 9 2 7 , ▁some ▁ 1 2 0 , 0 0 0 ▁individuals ▁in ▁ 9 ▁provinces ▁were ▁v acc in ated . ▁During ▁the ▁initial ▁uses , ▁all erg ic ▁re actions ▁were ▁reported ▁among ▁older ▁children ▁already ▁imm une ▁to ▁di ph ther ia . ▁Mol oney ▁developed ▁a ▁simple