606 
Analytical  Notes. 
Am,  Jour,  Pharm. 
Dec,  1888. 
The  above  results  would  indicate  an  average  of  3.21  per  cent,  of  nor- 
mal carbonate  in  the  commercial  product.  The  Pharmacopoeia  allows 
for  the  commercial  bicarbonate  about  5  per  cent,  of  carbonate,  and  for 
the  pure  a  limit  of  3  per  cent.  Accordingly  the  commercial  pro- 
duct is  almost  equal  to  the  requirements  of  the  pure,  and  the  major- 
ity of  the  samples  responded  to  same,  showing  the  superiority  of  the 
commercial  product  now  in  the  market. 
ANALYTICAL  NOTES. 
Abstracts  from  Theses. 
Assay  of  Benzoin. — Thos.  F.  Moody,  Ph.G.,  assayed  telf  commer- 
cial samples  of  benzoin,  by  digesting  and  afterward  boiling  in  each 
case  20  grams  with  10  gm.  of  slaked  lime  and  200  gm.  of  distilled 
water ;  the  decoction  was  filtered,  the  residue  well  washed  with  hot 
water,  the  filtrate  cooled  and  acidulated  with  hydrochloric  acid.  The 
precipitate  was  collected  on  a  filter,  washed  with  cold  water,  the  filtrate 
agitated  w^ith  chloroform,  the  chloroform  solution  evaporated  and  the 
residue  added  to  the  contents  on  the  filter.  After  drying,  the  benzoic 
acid  thus  obtained  was  weighed,  amounting  for  the  samples  examined 
to  2-14,  3-20,  3-40,  3-55,  4*0,  5-02,  5*50,  9-05,  9-72,  and  10-45  per 
cent.  In  each  case  the  presence  of  cinnamic  acid  was  shown  by  the 
bitter  almond  odor  produced  on  treatment  with  potassium  permanga- 
nate. The  author  also  states  that  he  observed  the  white  tears  to  yield 
a  much  smaller  amount  of  benzoic  acid  than  the  brown  mass,  but 
analytical  figures  are  not  given. 
Guaiac  Resin. — John  Herman  Rabenau,  Ph.G.,  examined  four 
commercial  specimens  with  the  following  results : 
Nos.  1.  2.  3.  4. 
Soluble  in  petroleum 
benzin   '006  per  cent.  '002  per  cent,  -01  per  cent. 
Soluble  in  ether   52-8      "      73-9  66-9  49*  per  cent. 
Treatment  of  ether  ex- 
tract with  KHO,  then 
HCl  ;precipitate 
weighed   29-4      "      54-7      "      28-1  307 
Portion  insoluble  in 
ether,  soluble  in  alco- 
hol  9-9      "        61      "       12-2      "  completely. 
Ash  from  original  resin,     6-45     "        4' 75     "        975     "  trace. 
