^ceXer!Som'}    Recent  Literature  Relating  to  Pharmacy.  597 
into  the  aldehyde  geranial,  which  is  identical  with  the  oil  present  in 
lemon  oil,  to  the  extent  of  7  per  cent.,  and  first  obtained  by  Schim- 
mel  &  Co.  as  citral,  as  well  as  by  Semmler  from  geranium  oil.  The 
closely  related  alcohol  linalol  and  its  acetate  are  important  constitu- 
ents of  oils  obtained  from  different  kinds  of  citrus.  Bergamot  oil 
contains  40  per  cent,  of  the  acetate,  orange  flower  oil  as  much,  to- 
gether with  30  per  cent,  linalol.  The  odorous  constituent  of  the 
violet  was  formerly  extracted  by  macerating  the  flowers  in  fat,  or  by 
exhausting  the  roots  of  Iris  florentina  with  ether.  Tiemann  and 
Kruger  found  in  this  ether  extract  the  glucoside  iridin,  and  from  it 
they  obtained  irigenin  and  iridic  acid,  as  well  as  irone,  a  ketone 
possessing  the  violet  odor.  In  1893  the  price  of  that  substance  was 
about  £750  per  pound,  and  only  a  few  pounds  were  made  yearly. 
But,  guided  by  purely  theoretical  considerations,  Tiemann  and 
Kruger  endeavored  to  obtain  irone,  or  a  similar  isomeric  substance, 
by  the  condensation  of  citral  with  acetone,  and  they  succeeded  in 
producing  pseudoionone,  an  oily  substance  that,  by  heating  with 
dilute  mineral  acids,  glycerin  and  water,  is  convertible  into  an 
isomer — ionone — which  has,  like  irone,  a  pronounced  violet  odor. 
The  production  of  ionone  then  increased  rapidly,  and  while  a  10 
per  cent,  solution  cost  formerly  £25  per  pound,  the  price  of  ionone 
is  now  much  reduced. 
Professor  Schmidt  concluded  his  very  interesting  account  by  point- 
ing out  that  German  chemical  industry  has  taken  the  lead  in  the 
production  of  the  materials  for  use  in  perfumery  and  pharmacy,  the 
award  of  prizes  to  the  four  firms  above  mentioned,  for  their  exhibits 
in  Paris,  being  a  convincing  testimony  to  their  capacity  in  that  re- 
spect. So  far  as  the  production  in  quantity  of  certain  odorous  sub- 
stances is  concerned,  it  may  be  concluded  that,  though  chemical 
industry  has  won  in  the  competition  with  Nature,  each  succeeding 
scientific  acquisition  serves  to  show  more  distinctly  how  many-sided 
Nature  is,  how  much  richer  she  is  in  agreeable-smelling  products  than 
chemical  industry,  and  how  inevitable  it  is  that  Nature  must  remain 
our  teacher  Editorial  in  Pharm.  Jour.,  1900,  p.  325. 
Nicotine  (0*0005-0 '005  gramme)  may  be  detected  by  adding  a  drop  of  for- 
maldehyde solution  (30  per  cent.)  and  then  a  drop  of  nitric  acid,  when  a  crim- 
son or  dark  red  color  is  produced. 
