540  State  Pharmaceutical  Associations.  J^S^fSo?" 
The  amount  of  change  one  of  these  unstable  substances  will 
undergo  when  subjected  to  certain  conditions  of  temperature  or 
atmosphere  is  a  problem  that  sometimes  needs  answering. 
Samples  of  exsiccated  salts  were  purchased  in  the  market  with 
the  view  of  making  experiments  as  to  the  amount  of  moisture  these 
substances  contained.  The  writer  says  that  U.S. P.  exsiccated  salts 
were  difficult  to  obtain,  that  in  most  cases  salts  known  as  "  dried 
and  powdered  "  were  substituted  without  anything  being  said  to 
the  purchaser;  that  is  to  say,  if  a  pharmacist  specifies  on  his  order, 
"  sodium  phosphate  exsiccated,"  he  will  receive  a  carton  usually 
marked  "  sodium  phosphate,  dried  and  powdered ; "  instead  of 
being  anhydrous,  as  required  by  the  Pharmacopoeia,  an  examination 
will  show  it  to  contain  from  15  to  20  per  cent,  of  moisture.  This 
substitution  by  the  manufacturer  has  become  so  common  that  many 
pharmacists  believe  the  terms  to  mean  the  same  thing,  a  condition 
which  some  manufacturers  encourage  by  having  the  word  "  exsic- 
cated "  as  a  synonym  of  "  dried  and  powdered,"  upon  the  package. 
The  following  salts  were  tested  for  the  percentage  of  moisture, 
which  proved  to  be  as  follows :  sodium  carbonate,  4.01  per  cent. ; 
sodium  phosphate,  17.70  per  cent.;  sodium  sulphate,  4.10  per  cent; 
ferrous  sulphate,  2.15  per  cent.;  exsiccated  alum,  9.9  per  cent. 
Further  experiments  were  carried  out  by  making  these  salts  per- 
fectly anhydrous  and  noting  the  amount  of  moisture  absorbed  in 
a  certain  period,  which  proved  to  be  considerable.  The  writer 
proves  beyond  doubt  the  necessity  of  the  pharmacist  investigating 
his  exsiccated  salts  when  he  buys  them,  and  the  necessity  of  keeping 
them  in  moisture-proof  containers  while  in  stock. — Pa.  Pharm. 
Assoc. 
The  Solubility  of  Official  Substances. 
By  M.  I.  Wilbert. 
The  author  states  that  one  of  the  problems  that  must  receive 
careful  consideration,  if  the  U.S. P.  is  to  become  the  accepted 
standard  for  materials  used  as  medicines  by  American  physicians,  is 
the  manner  of  stating  the  solubility  of  official  substances ;  that  the 
information  is  not,  at  the  present  time,  given  in  a  sufficiently  prac- 
tical manner  to  meet  the  needs  of  physicians,  or  of  being  memorized 
by  medical  or  pharmaceutical  students. 
He  says  that  the  assertion  that  apomorphine  hydrochloride  is 
soluble  in  39.5  parts  of  water,  in  38.2  parts  of  alcohol,  in  1864 
