A  VISIT  TO  A  SUSSEX  HOP  GARDEN. 
77 
further  distinctly  appreciable  quantity  of  nitrous  acid  is  given 
off.  The  fatty  acids  are  now  allowed  to  cool,  and  are  carefully 
removed  from  the  strongly-acid  and  richly-colored  solution  of 
terebic  acid.  The  cake  is  then  washed  by  melting  in  a  further 
quantity  of  nitric  acid.  When  cold,  it  is  dried  and  re-melted  at 
a  gentle  heat  till  acid  fumes  cease  to  be  given  off. 
The  resulting  cake  is  the  pure  fatty  acid  freed  from  resin,  the 
latter  being,  of  course,  indicated  by  the  loss.  The  author  has 
found  the  above  process  to  give  most  perfect  results  by  subject- 
ing soaps  of  known  composition  to  its  action. 
It  will  be  observed  that  a  correction  must  be  made  to  obtain 
the  exact  relative  proportions  of  fat  and  resin  originally  put  into 
the  soap-pan,  as  fats  on  being  decomposed  lose  about  4J  per 
cent,  of  their  original  weight — i.e.,  100  parts  tallow-glycer- 
ine —  95J  parts  fatty  acid.  Hence,  in  making  our  calculation, 
a  proportionate  addition  must  be  made  to  the  fatty  acid  before 
dividing  its  weight  by  that  of  the  resin  indicated.  This  process 
is  also  applicable  to  the  estimation  of  resin  as  an  adulterant  of 
beeswax.* — Loncl.  Chem.  JSfews,  Oct.  19,  1866. 
Soap  Works.  Sydney  Street,  Glasgow. 
A  VISIT  TO  A  SUSSEX  HOP  GARDEN. 
''Not  rural  sights  alone,  but  rural  sounds, 
Exhilarate  the  spirit,  and  restore 
The  tone  of  languid  nature." — Cowper. 
The  month  of  September  is  generally  a  favorite  part  of  the 
year,  as  the  fatiguing  heat  of  the  summer  sun  is  beginning  to 
relax  into  an  agreeable  warmth  more  congenial  to  our  feelings. 
The  operation  also  of  harvesting  the  corn  crops  has  been  per- 
formed, and  the  anxiety  of  many  a  paterfamilias,  respecting  a 
*  In  the  Chem.  Neivs,  November  2,  a  writer  criticizes  this  paper,  and 
believes  the  author  has  overlooked  the  action  of  NOo  on  the  fatty  acids 
as  a  source  of  error.  In  the  following  namber,  (Nov.  9,)  Mr.  Sutherland 
states  that  he  was  well  aware  of  the  apparent  theoretical  fallacies  of  his 
process,  but  that  in  practice  he  has  found  nitric  acid  to  attack  the  resin- 
ous acids  by  preference,  in  the  presence  of  the  fatty  acids.  Another 
writer  in  the  same  journal  claims  to  have  given  the  process  a  fair  trial, 
and  doubts  its  reliability. — Ed.  Am.  Jour.  Pharm. 
