440 
Reviews. 
/Am.  Jour.  Pharm. 
1  September,  1899. 
of  procedure  in  preparing  the  various  commercial  products.  During  the  past 
ten  years  there  has  been  witnessed,  particularly  in  the  researches  of  the 
ethereal  oils,  a  most  remarkable  development,  particularly  through  the  re- 
searches of  Professors  Wallach,  Baeyer  and  some  other  chemists.  Probably  no  one 
has  encouraged  the  scientific  study  of  the  essential  oils  to  such  an  extent,  and 
collated  and  distributed  so  much  information  relative  to  the  newer  scientific  devel- 
opments, and  the  substitutions  and  adulterations  of  the  essential  oils  than  have 
Messrs.  Schimmel  &  Co.,  and  no  one  is  so  familiar  with  all  that  is  known,  both  in 
a  commercial  and  scientific  sense,  in  regard  to  ethereal  oils  as  this  firm.  The 
preparation  of  the  various  natural  oils  is  still  regarded  by  some  as  an  agricul- 
tural industry,  but  the  chapter  by  Dr.  C.  von  Rechenberg,  in  this  new  book,  on 
the  theoretical  principles  for  the  production  of  essential  oils  by  means  of  dis- 
tillation with  steam,  indicates,  however,  that  a  study  of  the  laws  of  physics, 
particularly  of  heat,  has  much  to  do  in  the  securing  of  not  only  quantity,  but 
quality  of  product.  The  study  of  these  oils  for  purposes  of  identification,  detec- 
tion of  adulteration,  as  well  as  synthetic  preparation  and  imitation  requires,  as 
is  becoming  more  and  more  recognized,  the  most  carefully  trained  specialists 
in  this  subject.  Dr.  K.  Gildemeister,  one  of  the  editors  of  this  book,  is  well 
known  for  his  studies  in  this  direction.  The  historical  treatment  of  the  essen- 
tial oils  in  this  work  has  been  creditably  performed  by  the  able  pen  of  Dr.  Fr. 
Hoffmann. 
The  book  is  divided  into  four  parts  : 
I.  A  historical  treatment  of  the  spices  and  allied  products  is  given,  particularly 
during  ancient  times  and  the  middle  ages  ;  also  a  historical  treatment  of  essential 
oils  with  the  old  and  new  methods  and  apparatus  employed  in  obtaining  the 
same.  Numerous  well-made  illustrations  accompany  the  text,  and  we  have,  in 
the  136  pages  devoted  to  this  part  of  the  work,  a  very  comprehensive  review  of 
the  progress  in  the  discoveries  and  knowledge  pertaining  to  essential  oils,  as 
well  as  their  preparation  from  ancient  times  to  the  present  as  carried  out.  in  the 
largest  laboratories  devoted  entirely  to  this  subject  to-day. 
Part  II  is  devoted  to  a  general  consideration  of  the  subject  of  essential  oil?, 
and  several  specialists  have  written  certain  chapters.  Dr.  C.  von  Rechenberg 
has  written  a  special  chapter  on  the  "  Theoretische  Grundlage  der  Gewinuung 
der  atherischen  Oele  durch  Dampfdestillation,''  and  Dr.  J.  Helle  has  con- 
tributed an  article  on  "  Die  Haufiger  vorkommenden  Bestandtheile  der 
atherischen  Oele."  Two  other  important  chapters  complete  this  part  of  the 
book,  viz.:  one  on  the  testing  of  ethereal  oils  and  another  with  the  names  of 
the  plants,  arranged  according  to  Engler's  Syllabus  (1898),  that  yield  ethereal 
oils. 
Part  III,  comprising  over  600  pages,  is  devoted  to  a  special  considera- 
tion of  all  of  the  essential  oils.  It  may  be  truly  said  that  everything 
that  is  known  concerning  the  history,  origin  and  distribution  of  the 
plants  producing  the  oils  and  the  percentage  of  the  latter,  together  with 
their  general,  physical  and  chemical  properties,  as  well  as  chemical 
composition,  adulteration,  production  and  commercial  importance,  is  here 
given.  The  citation  of  the  important  literature,  together  with  the  other 
information  given,  makes  this  part  indispensable  to  every  one,  whether 
he  be  teacher,  manufacturer,  merchant  or  student,  who  has  anything  to 
do  with  the  study  or  handling  of  essential  oils.    The  character  of  the  work 
