How can one join the Royal Society of Chemistry as an AMRSC (or MRSC) without a referee?
From the help page of the Royal Society of Chemistry: 


  Who can be a referee for my membership application?
  
  Preferably a member of the Royal Society of Chemistry, however if you
  do not know a member who can act as referee, a member of a similar
  professional body can provide a reference. In some cases, a reference
  from a senior colleague, for example, your line manager or head of
  department will be acceptable.