132  Dr.  haygarth’s  Objervations  on  the 
whence  there  is  a perpendicular  fall  of  many  yards  from 
every  part  of  the  town. 
The  loofe  rock  on  which  the  town  is  built  abforbs 
moifture:  for  being  cut  into  filtering  fiones,  water  loon 
paflTes  through  its  pores.  The  principal  ftreets  that  meet 
in  the  centre  of  the  city,  are  deeply  excavated  out  of  the 
rock,  being  funk  fix  or  nine  feet  lower  than  the  lurface 
of  the  ground.  By  this  ftrudturc  the  foundations  of  the 
houfes  are  kept  perfectly  dry,  as  the  ftreets  quickly  drain 
off  the  water,  and  the  rock  abforbs  all  the  remaining 
moifture.  For  thefe  reafons  the  cellars  in  general  are 
dry,  a circumftance  that  greatly  contributes  to  health. 
Stagnant  water  in  a cellar  is  probably  very  often  the  un- 
fufpe<5ted  caufe  of  putrid  difeafes:  its  pernicious  influ- 
ence feems  to  refemble,  in  fome  degree,  that  of  bilge- 
water  in  a fhip. 
There  is  a form  of  building  peculiar  to  Chefter, 
called  the  Rows,  which  are  covered  galleries  that 
make  a complete  communication  between  moft  of 
the  principal  ftreets.  The  Rows  are  always  dry  and  clean 
even  in  wet  and  dirty  weather;  they  moderate  the  heat 
of  fummer,  and  the  coldnefs  of  winter.  Thefe  uncom- 
mon advantages  oftener  tempt  abroad  perfons  of  a deli- 
cate and  valetudinary  conftitution,  whether  they  be  en- 
gaged in  bufinefs  or  amufement ; by  Which  they  obtain 
i the 
