The British Broadcasting Company, (BBC) lost a number of early TV programs which are now thought to be historically significant and very much desired by fans of some programs. This is true of a number of other networks, but few fans are as fanatic as those of the continuing Sci-Fi series Dr. Who. Recently two of the more than 100 lost William Hartnell and Patrick Troughton Dr. Who episodes have been located.
http://www.bbc.co.uk/news/entertainment-arts-16136521
The BBC would very much like to locate the missing 100 or so episodes dating from 1965, 66, and 67.
Old TV show tapes are likely to turn up any place since they were routinely shipped from station to station physically back in the days before high speed satellite connections.
If you were wondering just why something so potentially valuable could have been simply wiped and the original tapes reused, I can explain from personal experience.
When I worked at WGBH-TV (PBS) in Boston, one of my jobs was in the traffic department which, in TV and radio means not just handling mail but more importantly, scheduling, shipping, and archiving programs.
In those days (1960’s) the tapes were of only generally good quality and as I recall station engineers had to certify each one as being good enough to record important programs such as those produced at WGBH, which included The French Chef and the Boston Pops and Symphony broadcasts.
Not only were the giant reels of magnetic tape expensive to begin with, the certification process meant that each one had to be recorded once in blank and then actually viewed by an engineer to see how many dropouts (“sparklies”) showed up in what should have been blank video.
I remember driving loads of the old Symphony and, I think Pops video tapes to be archived at Boston University so I know we kept a lot of programs.
But since the tapes had to be certified individually they were very valuable even blank so I can understand why some networks routinely wiped old programs to reuse the tape – I presume this is what is thought to have happened to the BBC Dr. Who episodes, although I have no personal knowledge of the kind of tape they used.