In reply to Pete Houghton:
Old 'phones used to have a long coiled cord connecting the bit you spoke into to the box on the table or wall with the magic in, like this:
http://www.samhallas.co.uk/collection/bits_trimphone.htm
This cord had two purposes, it stopped you nicking the easily portable small end that couldn't be screwed down, and it was designed to bounce the sound around as it travelled from the magic box to your ear so that all the sharp edges got knocked off giving a very muffled quality to the sound, thus rendering it obvious you were talking to someone a long way away so that you wouldn't waste time searching around the room to find where the person you were talking to was hiding.
There endeth today's history lesson.