Epsom  Salt  versus  Strawberries.  323 
tion,  by  simply  dissolving  15  grams  of  Epsom  salt  and  8  grams  of 
common  salt  in  a  champagne  bottle  (quart)  full  of  water.1 
In  how  far  the  presence  of  the  common  salt  may  be  essential  to  the 
efficacy  of  this  mixture  I  am  not  prepared  to  say.  I  added  it  on  the 
conjecture  that  a  solution  containing  a  chloride  as  well  as  a  magnesium 
compound  might  perhaps  serve  a  better  purpose  than  sulphate  of  mag- 
nesium by  itself. 
The  common  salt  has  at  least  the  merit  of  abating  or  disguising  to 
an  appreciable  extent  the  disagreeable  taste2  of  the  Epsom  salt. 
As  for  the  mode  of  action  of  these  small  doses  of  saline  matters,  it 
would  seem  to  admit  of  ready  explanation  on  the  old  theory  that  the 
salts  tend  to  detain  the  water  in  which  they  are  held  dissolved.  That 
is  to  say,  the  salts  hinder  the  water  from  passing  through  the  walls  of 
the  intestines  by  way  of  osmose,  and  consequently  carry  into  the  rec- 
tum a  certain  amount  of  water,  which  but  for  the  presence  of  the  salts 
would  naturally  have  been  discharged  through  the  skin.  Since  the  mag- 
nesium salt  is  a  crystalloid  and  not  a  colloid  body,  part  of  it  undoubt- 
edly passes  into  the  blood,  and  some  of  it  passes  through  the  kidneys 
and  is  discharged  with  the  urine  ;  but  a  certain  quantity  does,  neverthe- 
less, go  into  the  rectum,  carrying  with  it  enough  water  to  keep  the 
contents  of  that  receptacle  moist. 
It  is  to  be  borne  in  mind,  of  course,  that  in  using  these  continuous 
small  doses  of  the  magnesium  salt  we  undoubtedly  produce  some  other 
physiological  effects  which  are  known  to  attend  the  use  of  this  medica- 
1  A  small  wine-glassful  of  this  solution  may  be  taken  on  going  to  bed  at  night, 
on  getting  up  in  the  morning,  in  the  middle  of  the  afternoon,  and  of  the  forenoon 
also,  if  need  be;  or  more  frequently  still,  in  case  the  foregoing  doses  should  prove 
to  be  insufficient.  Sometimes,  on  the  other  hand,  a  couple  of  doses  will  be  all-suf- 
ficient, taken  at  night  and  morning. 
It  may  here  be  said  that  in  a  preliminary  trial,  or  mixture  of  100  grams  Epsom 
salt,  S  grams  crystallized  chloride  of  magnesium,  12  grams  Glauber  salt  and  8  grams 
common  salt,  to  the  quart  of  water,  was  found  to  be  too  strong. 
It  is  noteworthy  that  the  solution  described  in  the  text  contains  a  much  smaller 
amount  of  saline  matter  than  the  sum  of  the  matters  contained  in  the  Friedrichshall 
water,  as  indicated  by  the  analysis  above  cited. 
2 1  have  noticed  in  several  instances  that  the  taste  of  the  mixed  solution  has 
improved  on  standing;  that  is  to  say,  a  slight  but  peculiar  disagreeable  taste  was 
noticeabele  in  the  freshly  prepared  solutions  that  could  not  be  detected  in  solutions 
that  had  been  kept  a  week  or  more. 
