United Pres ’ Rneeial.Chicago, May 13. -Jack Johnsonwill take the witness stand late today and delend himself against charges of white slave law violations. The examination of witnessesbegan today,Harney Furey. a colored trainer, formerly in Johnson’h employ, was the lirst witness. He told of autotripH he had made with Johnson through the east and denied that on any of these occasions did Belle Bchriober, the principal witness against the blaek man, accompanyli i in