| Show SOVIET REVOLUTION THREATENED IN CUBA CUBAt t Communists s Urge Uprising on Day of Massacre HAVANA Aug 7 Communist JP-Communist ff manifestos were circulated today the ann anniversary ersary of Cubas Cuba's day of massacre calling for lor a revolution and the establishment of a soviet government One year ago ngo today 23 Cubans were killed when forces of Gerardo M Machado Machado Ma- Ma chado then president fired on crowds prematurely celebrating Machado's Machados Machados Machado's Ma Ma- chados chado's downfall Mach Machado do fled the palace five days later August 12 a and d the communist circulars call for tor an uprising on that date Persistent but rumors of revolution are buzzing about the capital Soldiers Soldiers' arrested Salvador Diaz Verson a a. former chief of ot J police olic under under un un- un der President ex-President Ramon Grau San SanMartin SanMartin SanMartin Martin but refused to disclose the nature of the charges against him Three Americans Frederick Will Will- cox Arthur B. B Needham B Needham and Colonel Colonel Colo Cole nel nd Hoffman HoHman are held in Prin Principe ipe p prison ison on charges of selling arms to Cubans |