Silver-grey balloon clusters at very high altitude, at high speed

Per Mr. Davenport's request, I am submitting this report about seeing some balloon-like objects.
 From 1984 through 1987, while living in the Monterey Bay Area, I observed several times what appeared to be flights of balloon clusters at very high altitudes passing eastward over the Central California Coast.
 Most were too far away and too high to see much, even with 7x binoculars.
Only one time did they pass directly overhead and seemed close enough to see them better.
 The clusters appeared to be several silver-gray, featureless balloons in tight formations and appeared to be straight eastward moving very rapidly, like a jet. They also seemed to be moving around, rotating around each other in rather unballoon-like ways but I am uncertain of this because of they were so far away.
 I did not think much of these sightings, assuming that they were some sort of new fancy style of balloon, travelling in the jet stream, until I found out that others had seen very similar objects from relatively close by.
Witness indicates that the date of the sighting is approximate.  One of three seemingly high-quality sighting reports from same source.  PD