Jury Indicts Billings Knife Slayer of BoySACRAMENTO, Calif. (UP) — Thomas Lynn Johnston, apprentice embalmer accused of the wanton knifing of a seven-year-old boy, has been indicted for murder by a grand- jury that deliberated less * than an hour.Johnston, 24, of Billings, Mont., , was confined in his city jail cell , to await superior court arraign- i ment on the charge, probably Wednesday or Thursday.Jailers said he slept quietly after i his indictment He was held in a 1 common tank with 20 other prisoners, but was stripped of his belt, shoe laces, tie and the like to pre- \ vent any attempt at suicide. Police j said it was a routine precaution, iJohnston previously admitted knifing Ronald Wendorf in a Sac- 1 ramento theater Feb. 5 “to see i what would happen.” He did not appear before the special session of the 19-member grand jury.Witness before the panel included the autopsy surgeon; William B. Sanderson, assistant theater manager, who held Johnston until police arrived; and the first officers on the. scene.