172       Loss  of  Weight  in  Drying  Air-dry  Drugs,  {A^r°X'?m™' 
in  the  retort  was  deep  red,  and  ether  dissolved  from  it  an  olive-brown 
amorphous  mass,  becoming  violet  by  alkalies.  No  better  results  were 
obtained  on  saponifying  the  oil  with  potassa,  removing  the  soap  by 
salt,  acidulating  with  acetic  acid  and  treating  with  ether ;  the  residue 
was  acrid,  amorphous,  of  an  acid  reaction,  colored  violet  by  alkalies 
.and  stained  the  hands. 
Commercial  benzole  was  not  employed  by  the  author,  because  he 
[  observed  it  to  leave  a  crystalline  residue  on  spontaneous  evaporation. 
Air-dry  bark  yielded  5*3  per  cent,  of  ashes,  containing  aluminium, 
magnesium,  calcium,  potassium  and  sodium,  combined  with  carbonic, 
sulphuric,  hydrochloric,  phosphoric  and  silicic  acids. 
Note  by  the  Editor. — The  results  obtained  by  Messrs.  Thiebaud 
i  and  Dawson  leave  no  doubt  that  the  juglandic  acid  of  the  former  is 
identical  with  the  nucin  of  A.  Vogel,  Jun.,  and  Reischauer  (see 
'Gmelin's  Chemistry,  Cav.  edit.,  vol.  xvii,  p  20),  obtained  from  green 
walnut  peel,  and  which  is  very  readily  altered  in  the  presence  of  that 
principle,  which  in  contact  with  the  air,  rapidly  becomes  brown-black, 
and  which  J.  A.  Buchner*  named  juglandic  acid,  but  he  did  not  succeed 
in  isolating  it.  Nucin  being  sublimable  at  a  temperature  exceeding 
80°  C.  (176°  F.),  its  appearance  in  the  watery  distillate  from  the 
bark  is  easily  accounted  for,  so  that  the  volatile  acid  of  Dawson  and 
Thiebaud  must  be  identical  with  the  juglandic  acid  of  the  latter,  as 
|  proven  by  the  former  by  the  behavior  to  alkalies.  According  to 
Reischauer  and  Vogel,  subacetate  of  lead  and  alkaline  borates  and 
phosphates  impart  to  nucin  a  beautiful  purple  red  color,  the  same  as 
caustic  alkalies. 
ON  THE  LOSS  OF  WEIGHT  BY  THE  DRYING  OF  AIR-DRY 
DRUGS. 
By  George  W.  Kennedy,  G.  P. 
In  the  April  number  of  the  "Journal"  of  1872,  page  156,  will  be 
i  found  an  article  by  the  writer  on  the  amount  of  moisture  contained  in 
!  air-dry  drugs.    The  experiments  were  made  during  the  months  of 
January  and  February,  and  only  show  the  loss  and  re-absorption  for 
;  those  two  months. 
*Buchner's  Repertorium,  1843  ;  lxxix,  355. 
