344 
Examination  of  Glycerins. 
I  Am.  Jour.  Pharm. 
(.       Aug.,  1875. 
EXAMINATION  OF  GLYCERINS. 
BY  THOS.   ALEX.    CHEATHAM,  PH.  G. 
[Abstract  from  an  Inaugural  Essay.) 
Of  the  five  specimens  of  pure  glycerin  examined,  the  table  given 
below  shows  the  result.  The  manner  of  proceeding  was  as  follows  : 
The  glycerins  when  purchased  had  on  each  bottle  the  manufacturer's 
labels,  which  were  not  removed  during  the  examination,  so  as  to  ascer- 
tain of  each  its  individual  merits.  Their  specific  gravities  were  ob- 
tained by  means  of  the  specific  gravity  bottle,  the  usual  precautions 
being  observed.  Their  color  was  then  noted,  after  which  their  odor 
when  cold  and  when  heated  to  the  boiling  point  was  ascertained.  The 
reagents  were  then  applied  to  the  glycerins  in  a  dilute  condition  and 
their  effects  noted  immediately  after  addition,  five  minutes  afterwards, 
three  hours  afterwards  and  twenty-four  hours  afterwards.  Five  spec- 
imens of  commercial  glycerin  were  also  examined,  and  the  observations 
were  made  in  a  similar  manner. 
Of  all  the  pure  glycerins  examined,  that  of  Henry  Bower  justly 
heads  the  list  for  purity  and  general  appearance.  The  plan  of  exam- 
ination was  suggested  by  two  papers  read  by  Prof.  Joseph  P.  Reming- 
ton, before  the  American  Pharmaceutical  Association,  in  1870  and 
187 1,  and  published  in  their  proceedings  for  those  years. 
The  following  table  shows  the  condition  of  the  glycerins  24  hours 
after  adding  the  reagents  : 
Table  of  Results. 
IMannfactiirer . 
Sp.  gravity. 
Colors. 
Odor,  cold 
Odor,  heated. 
I'250 
Colorless. 
No  odor. 
Very  slightly  empyreu- 
matic. 
i'255 
Colorless. 
No  odor. 
Empyreumatic. 
i*255 
Slight 
Color. 
No  odor. 
Slightly  empyreumatic. 
1-249 
Colorless. 
Fatty. 
Slightly  fatty. 
1-248 
Colorless. 
Empyreu- 
matic. 
Empyreumatic. 
Varying. 
1-246  to  i"256 
Colorless. 
Varying. 
Varying  ;  empyreuma- 
tic and  fatty. 
