DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE PUBLIC HEALTH SERVICE 25 Jajiuarli l@EtO National lostit-ats of Mental Health A"Ictiog, Resc2imb, Ceattf U.L pubue HeLub 54m,. cc Hospital .;7or vour in@'cr-altlon I ai7 i enclo s-,- ooy a 'e'ter L 2 to Or 3!rc!,-@er, o--" '-'-andoz, Irco@,oora"-ed, and copies o.r three t=-bl;@s explaT-;-Li.no- the results o@r our studies t-o date or, tolerance and cross tolerance bet-.4een siloci7bTr, and 2 as well as clur plars A'or p ation "-his work in the inir.-ediate J'uture. Sincerel%r tours, Abraharn. 9 Acting Direc@Lor r n 'i@:-'nclosures