They did not have scanners and PC's back then,,and they could not zoom in and look close quite so easily,, but they did have excellent photolabs to enlarge images.. The most outrageous clue you can imagine arrived in this envelope,,, the man seemingly had sent his own voice,, they also had over 700 hundred written words,,,his rare blood type,,,and now he very kindly sends them a sample of his printing as well... You would think he was inviting Oldfield for tea and biscuits,, the clues were so hot... Oldfield remarked "I hope he sends his photo with his name and address on the back next time"... A voice that had never been heard before arrived in an envelope with printing which had never been seen before,,,and it is clear that the writer was well aware of this and helps out by signing the easily identifiable Jack the Ripper signature on the inside of the envelope... The cruel twist was that the tape announced another threat to kill in a few months time,, the Police knew he kept his last two promises and launched an enormous manhunt after that man in Sunderland.. With the information they had,, they expected to get him very quickly and it should have been so,, but against all reasonable expectations they failed to find that man and another girl was killed just as predicted.. It was not Oldfield or Gregory who sent them to scour the N/E bare,, it was that dammed clever clogs killer in Yorkshire who sent them there,,, and so I ask if there is not something wrong with this picture of a serial killer guiding the very manhunt that was after him,, that the Wearside man could not be found says there was.. If there is one thing that warrants the closest examination and consideration it is the Sunderland tape and the envelope it arrived in,, and it looks rite dodgy to me,, like two persons were mixin it up.. The question now,, is why,, disguise the handwriting and printing but send an easy to recognise voice..?