2-12  Dr.  white’s  Experiments 
the  lens  pdujlris  might  have  grown  putrid,  and  hurt  the 
air. 
exp.  xx.  Some  of  the  fofs  water  was  next  tried;  fo 
foul  as  to  depofit  a muddy  fediment  upon  Handing. 
In  one  experiment  the  air  was  reduced  from  62°  to 
5 8°;  in  another,  from  6a?  to  5 7 0 ; in  a third,  from  6o° 
to  56°. 
exp.  xxi.  It  has  been  obferved  by  thofe  phylicians 
who  have  had  the  moft  opportunities  of  being  ac- 
quainted with  the  difeafes  peculiar  to  low,  ftagnant,  and 
fenny  fituations,  that  they  feldom  begin  to  appear  until 
the  water  is  fo  far  evaporated,  that  the  black  and  flimy 
mud  begins  to  appear.  In  order  to  know  this,  the  fol- 
lowing experiments  were  made. 
Two  ounces  of  the  black  ftinking  mud  of  the  fofs  was 
put  into  the  eight-ounce  phial  of  air;  being  clofed,  they 
were  fuffered  to  remain  together  twelve  hours.  The  air 
in  twelve  trials  being  put  to  the  teft,  the  refults  were  as 
follow. 
In  feven  experiments  the  air  was  reduced  from  62°  to 
34°;  in  three,  from  62°  to  36°;  in  two  others,  from  603 
to  35°. 
Thefe  are  convincing  examples  of  the  noxious  effects 
of  the  effluvia  from  putrid  bogs  and  marffles.  Although 
i was  perfectly  convinced  of  this  by  the  authorities  of 
< - .1  -a  Sir 
1 
