% Sir  william  Hamilton’s  Account  of 
juft  made  during  a five-days  raoft  delightful  paflage  up 
the  Rhine  from  Bonn  to  Mayence.  The  firft  certain 
token  of  volcanos  having  exifted  in  this  country  was  evi- 
dent to  me  in  the  court  of  the  palace  of  the  Eledior- 
palatine  at  DufleldorfF,  which  is  at  this  moment  new 
paving  with  a lava  exadtly  like  that  of  Etna  and  Vefu- 
vius.  Upon  enquiry  I was  told,  that  it  came  from  a 
quarry  belonging  to  the  fame  Elector  at  Unkel,  between 
Bonn  and  Coblenz.  When  I arrived  at  the  gates  of  Co- 
logne, I was  ftruck  with  the  fight  of  numberlefs  bafaltic 
columns  inferted  in  the  walls  of  the  town;  and  I re- 
marked, that  columns  of  the  fame  fort  were  univerfally 
ufed  as  polls  in  the  ftreets,  and  at  every  door ; they  are 
chiefly  pentagonal,,  but  fome  are  hexagonal,  and  a few 
have  only  four  fides ; they  are  very  like  the  bafaltes  of 
the  Giants  Caufeway,  but  without  their  regular  articula- 
tions. I was  informed,  that  they  came  likewife  from  the 
Unkel  quarry;  and  that  the  town  of  Cologne  is  in  pof- 
feffion  of  an  ancient  right  to  as  much  ftone  from  that 
quarry  as  may  be  wanted  for  its  own  ufe.  I perceived 
likewife,  that  the  walls  of  molt  of  the  ancient  buildings 
in  the  town  of  Cologne  were  of  a tuffa  exactly  refem- 
bling  that  of  Naples  and  its  environs.  This  fpecies  of 
ftone,  as  I was  informed,  abounded  on  the  banks  of  the 
Rhine,  between  Bonn  and  Coblenz : thefe  circumftances 
4 made 
