Am.  Jour.  Pharm. 
June,  1878. 
Mate^  or  Paraguay  Tea. 
281 
aid  of  heat  to  the  specular  form  ;  auric  chloride  is  decomposed  in  the 
cold  ;  barium  nitrate  gives  a  faint  but  immediate  yellowish-white  pre- 
cipitate ;  stannous  chloride  gives  a  white  precipitate  ;  tartrate  of  anti- 
mony and  potassium  produces  no  precipitate;  sulphate  of  quinia  and  sul- 
phate of  cinchonia  both  produce  white  precipitates  ;  gelatin  gives  no 
precipitate  ;  acetate  of  lead  gives  a  yellowish-white  precipitate  ;  per- 
manganate of  potassium  in  solution  is  immediately  decolorized  ; 
molybdate  of  ammonium  produces  a  brownish-red,  which  is  changed  to 
yellow  by  oxalic  acid  ;  morphia  gives  a  slight  precipitate  on  standing  ; 
strychnia  gives  a  white  precipitate  ;  aconitia  gives  no  precipitate  ;  vera- 
tria  with  hydrochloric  acid  gives  a  white  precipitate  \  salicin  and 
santonin  give  no  precipitate  ;  piperina  with  hydrochloric  acid,  color 
lightened  but  no  precipitate  ;  sulphuric  acid,  aided  by  heat,  changes  a 
concentrated  solution  to  a  deep  red. 
Caffeina. — The  following  process  was  employed  for  the  determination 
of  the  quantity  of  caffeina  :  10  grams  of  powdered  mate*  and  4  grams 
calcined  magnesia  were  boiled  for  half  an  hour  with  500  cc.  distilled 
water,  and  filtered  while  hot,  the  residue  and  the  filter  returned  to  the 
flask,  500  cc.  water  added,  and  again  boiled  for  twenty  minutes  ;  then 
filtered  and  boiling  water  poured  on  the  filter  until  the  filtrate  passed 
colorless  and  tasteless.  The  filtrate  was  then  evaporated  at  a  moderate 
heat  over  a  naked  fire  until  reduced  to  200  cc,  and  then  10  grams  of 
powdered  glass  and  1  gram  calcined  magnesia  were  added,  and  the 
evaporation  continued  on  a  water-bath  to  dryness.  The  dry  residue 
was  then  finely  powdered  and  placed  in  a  small  flask  with  30  grams 
chloroform,  and  boiled  for  a  few  minutes,  and  then  filtered  through  a 
funnel,  the  neck  of  which  was  closed  with  cotton,  and  over  this  was 
placed  a  layer  of  powdered  glass.  The  residue  in  the  flask  was 
treated  with  fresh  portions  of  chloroform  until  the  caffeina  was  all  dis- 
solved out.  The  chloroform  was  then  allowed  to  evaporate  sponta- 
neously in  a  weighed  capsule,  yielding  the  caffeina  in  fine  silky  form 
on  the  bottom  and  sides  of  the  capsule — perfectly  white  if  the  chlo- 
roform solution  had  been  allowed  to  cool  before  filtration,  but  if 
filtered  hot  the  caffeina  was  very  slightly  tinted  of  a  greenish  color. 
The  amount  of  caffeina  obtained  from  each  sample  will  be  found  in 
table  No.  I. 
The  Ash. — The  determination  of  the  total,  the  soluble  and  the 
