POISONOUS  EFFECT  FROM  COPPER  FOUNTAINS. 
demanded  investigation,  was  a  white  precipitate,  the  carbonate  of 
lead.  This  was  found,  to  a  greater  or  less  amount,  in  most  of 
the  waters  examined. 
In  the  quart  whence  the  grain  and  a  half  of  copper  was  ob- 
tained, 0.65  of  a  grain  of  metallic  lead  was  found. 
The  chief  source  of  this  impregnation  is  the  lead  pipe  used  in 
many  fountains  to  convey  the  carbonated  water  from  the  con- 
densers to  the  jet. 
It  is  an  established  fact,  that  the  free  carbonic  acid  found  in 
spring  waters,  is  capable  of  dissolving  or  facilitating  the  solution 
of  many  of  the  salts  of  lead,  such  as  are  found  encrusting  lead- 
pipes  which  have  been  used  for  conducting  said  waters. 
By  the  investigations  of  Dr.  Ellet,  published  in  this  .city  last 
year,  it  was  clearly  shown  that  even  the  trivial  amount  of  car- 
bonic acid  found  in  Croton  water,  is  sufficient  to  act  upon  the 
lead-pipes. 
This  lead  may  be  readily  found  in  any  kettle  which  has  been 
used  for  boiling  the  Croton  water  passed  through  a  lead-pipe,  by 
adding  a  little  acetic  acid  to  it.  The  acetate  of  lead  will  respond 
to  sulphuretted  hydrogen,  by  assuming  a  black  tint  (the  sulphuret 
of  lead,)  or  a  yellow  tint  with  the  iodide  of  potassium,  etc. 
Since  carbonic  acid  is  possessed  of  such  solvent  powers,  soda 
water,  which  is  surcharged  with  it,  must  become  poisonously  con- 
taminated by  contact  with  lead,  either  in  the  pipes  or  the  solder- 
ing ;  and  as  much  of  the  tin  of  commerce  is  alloyed  with  lead, 
even  this  metal,  to  which  we  look  for  protection,  may  be  another 
source  of  evil. 
Many  are  impressed  with  the  belief  that  the  first  few  glasses 
may  be  impregnated  with  lead  to  an  injurious  extent ;  and  hence 
the  custom,  in  the  more  respectable  establishments,  of  discarding 
the  soda  water  which  is  first  drawn,  and  has  lain  in  the  tube  over 
night. 
Wherever  lead  pipes  are  used  to  conduct  the  water  to  the  jet 
and  especially  where,  in  order  to  secure  a  cool  draught,  from 
thirty  to  sixty  feet  of  lead  pipe  are  coiled  in  a  tank  and  covered 
with  ice,  the  highly  acid  liquid  must  necessarily  dissolve  the 
metal,  and  communicate  the  poison  to  all  contained  within  the 
condenser. 
These  remarks  are  not  applicable  to  pipes  of  pure  tin,  or  of 
lead  properly  coated  with  tin. 
