■Am.  Jour.  Phat-m. 
Mar.,  1883. 
'•|     Turpentine:  its  Nature  and  Adulterations. 
149 
It  is  the  product  of  Finns  sylvestris,  but  I  have  not  been  able  to  ascertain 
whether  the  turpentine  is  specially  collected,  or  is  a  mere  by-product. 
According  to  one  account  which  I  have  received,  the  waste  timber  is  piled 
into  heaps  and  a  fire  lighted ;  the  resinous  matter  which  drains  away  is 
then  collected  and  the  turpentine  extracted  from  it  by  distillation. 
Different  samples  are  remarkably  different  in  their  optical  character,  as 
the  following  numbers  show  : 
Excepting  the  first  four,  all  these  samples  were  drawn  from  single  barrels, 
:and  were  obligingly  furnished  to  me  by  Mr.  Kingzett. 
Russian  turpentine  has  been  shown  by  Tilden,  "  Chem.  Soc.  Trans." 
1878-80,  to  consist  of  a  peculiar  CjoHig  hydrocarbon,  the  so-called  Sylvestrene 
of  Atterberg  (Ber.  10,  1202),  and  of  an  isomeride  possessing  the  character 
ot  American  turpentine.  Sylvestrene,  according  to  these  authors,  has  a 
specific  rotatory  power  of  (a^)  =  19'5°  (Atterberg),  19*6°  ^Tilden),  that  of  the 
associated  hydrocarbon  being  36*3°  (Atterberg).  In  conformation  of  the 
assumption  that  one  of  the  constituents  of  Russian  turj^entine  is  probably 
identical  with  the  main  constituent  of  American  turpentine,  I  may  men- 
tion that  I  have  separated  from  the  latter  by  fractional  distillation  a  portion 
having  a  rotatory  power  per  200  mm.  of  no  less  than  49°  34^,  and  that  on 
several  occasions,  by  submitting  American  turpentine  to  air  oxidation,  and 
afterwards  distilling  off  the  unaltered  hydrocarbon  by  steam,  I  have 
obtained  products  of  considerably  higher  rotatory  power  than  the  original 
oils.  I  have  also  examined  several  samples  received  from  Mr.  Kingzett  of 
the  hydrocarbon  carried  over  by  the  air  current  during  the  air  oxidation 
of  Russian  turpentine.  In  most  cases  these  have  been  almost  free  from 
sylvestrene,  and  have  exhibited  a  higher  rotatory  power  than  the  original 
crude  turpentine  from  which  they  were  derived. 
The  numbers  above  given  fluctuate  within  wide  limits,  and  are  of  interest 
as  indicating  that  the  proportions  in  which  the  two  recognized  constitu- 
ents of  Russian  turpentine  are  present  probably  vary  considerably,  and 
also  that  other  perhaps  isomeric  hj^drocarbons  are  mixed  with  them  ;  they 
serve  to  confirm  the  idea  that  American  turpentine  is  also  a  mixture  of 
isomeric  hydrocarbons.  I  may  add  that  certain  observations  even  lead  m© 
to  think  it  not  unlikely  that  the  low  dextro-rotatory  power  of  American 
turpentine  is  due  to  the  presence  of  a  Isevo-rotatory  terpene;  this  would 
serve  to  explain  the  difference  in  optical  character  of  products  from  differ- 
ent localities.  The  comparative  study  of  American  turpentine — and  indeed 
■generally  of  oils  containing  CioHig  hydrocarbons — from  this  point  of  view, 
I  think  deserves  attention  ;  variations  in  climatic  and  other  conditions 
may  have  led  to  a  gradual  differentiation  both  in  botanical  and  physiological 
character  of  a  single  parent  stock. 
a,(per  200  mm.)  :=36°  29^ 
44°  11^ 
41°  0^ 
35°  28^ 
30°  42^ 
35°  20^ 
38°  6^ 
45°  10^ 
38°  4^ 
40°  42^ 
46°  45^ 
36°  4^ 
37°  5^ 
42°  10^ 
39°  52^ 
30°  10^ 
