112 
GLEANINGS  FROM  GERMAN  JOURNALS. 
Corydalia  has  again  been  investigated  by  G.  Leube,  jun.  He 
has  likewise  been  unable  to  obtain  crystallizable  compounds  with 
acids,  found  Miiller's  ultimate  analysis  correct,  and  proved  the 
alkaloid  to  be  anhydrous  when  dried  at  50^  C.  (132^  F.)  The 
equivalent  weight  was  calculated  from  the  yellow  precipitate  with 
bichloride  of  platinum  —4720  (0  =  100]  and  from  the  white 
precipitate  with  bichloride  of  mercury  =4672. 
Its  formula  is  C^g  Hgg  NO^,  the  equivalent  weight  4687.5. 
(Wittst.  V.  Schr.  ix.  524—527.) 
PJiospJio-moIyhdate  of  ammonia — E.  Spiess,  of  Munich,  and 
Professor  Y.  Eggertz,  of  Fahlun,  corroborate  Nuntzinger's  ana- 
lysis of  this  compound,  who  calculated  after  drying  at  212^  F. 
the  following  formula  :  4(H^N0, 10MoO3)+(H4 NO-h[8Mo  O3, 
2P0J)=:3.577  NH,0,  3.962  PO^,  92.461  M0O3.— (Wittst.  ^- 
Schrift  ix.  527—429.) 
Fat  in  urine  was  observed  by  Landerer  in  the  urine  of  a 
young  man  sulfering  from  tuberculosis  ;  it  had  an  acid  reaction. 
(Wittst.  V.  Schr.  ix.  534.) 
On  emery — The  trade  in  emery  is  not,  as  formerly,  monopo- 
lized by  the  Greek  government, which  nowlevies  a  tax  of  5  drachms 
per  hundred  weight  when  exported.  Other  hard  minerals  are  some- 
times fraudulently  substituted  for  it,  to  detect  which,  and  to  de- 
termine the  value  of  the  emery,  the  following  method  is  em- 
ployed in  Smyrna  :  A  plate  of  glass  of  know^n  weight  is  rubbed 
with  a  certain  quantity  of  the  emery  until  it  has  no  further  ef- 
fect ;  the  lighter  the  glass  has  become,  the  better  is  the  quality 
of  the  emery.  The  emery  diggings  of  the  government  are  on 
the  island  of  Naxos.  A  ferruginous  clay  silicate  has  lately  been 
discovered  upon  the  island  of  Skyno,  which  is  not  inferior  in 
hardness  to  emery.— (Wittst.  V.  Schr.  ix.  535). 
Estimation  of  nitric  acid. — Fresenius  dissolved  a  known 
weight  of  fine  piano-wire  in  an  excess  of  muriatic  acid,  contain- 
ed in  a  retort  through  which  hydrogen  passes  ;  the  nitrate  is 
afterwards  thrown  in,  and  after  the  dark  color  has  disappeared, 
the  amount  of  protoxide  in  the  cooled  solution  is  determined 
by  permanganate  of  potassa.  The  quantity  of  peroxide  is  now 
easily  calculated,  and  from  it  the  amount  of  nitric  acid  by  which 
