Non-confirmation of reported HI clouds without optical counterparts in the Hercules Cluster

21 cm H i line observations were made with the Arecibo Gregorian telescope of 9 H i clouds in the Hercules Cluster which were reported as tenative detections in a VLA H i study of the cluster (Dickey 1997) and for which our deep CCD imaging failed to find any optical counterparts. No sensitive observations could be made of one of these (sw-174) due to the presence of a close-by strong continuum source. The other 8 tentative H i detections were not confirmed by the Arecibo H i measurements. The CCD images did reveal faint, low surface brightness counterparts near the centres of two other VLA H i sources invisible on the Palomar Sky Survey, sw-103