Am.  Jour.  Pharm.  ) 
Sept.,  1879.  J 
Researches  on  Albumin, 
463 
cent,  had  been  eliminated  ;  this  number  was  never  exceeded.  At  1200 
in  the  autoclave,  2*2  per  cent,  of  nitrogen  was  evolved  by  digestion 
during  six  or  eight  hours  ;  at  1500,  with  only  twice  its  weight  of 
baryta,  3*1  per  cent,  was  obtained  ;  whilst  between  1500  and  1800, 
with  three  parts  of  baryta  for  24  hours,  3*95  per  cent,  was  disengaged, 
and  the  limit  of  4*0  per  cent,  was  not  exceeded  even  by  heating  with 
six  parts  of  baryta  for  six  or  eight  days.  These  three  limits  indicate 
clearly  three  successive  and  different  stages  of  decomposition. 
Insoluble  Barium  Salts. — The  quantity  of  this  deposit  like  the  ammo- 
nia varies  with  the  temperature  and  with  the  proportion  of  baryta  used; 
in  composition  as  well  as  in  weight,  it  undoubtedly  bears  a  direct  rela- 
tion to  the  quantity  of  ammoniacal  nitrogen  disengaged.  It  consists 
mainly  of  barium  carbonate  and  oxalate,  with  a  certain  amount  of 
barium  phosphate  and  sulphate  ;  the  proportions  of  the  two  former, 
the  only  important  elements  in  the  mixture,  were  as  follows  :  From 
100  grams  of  albumin — 
N. 
BaC03. 
BaC2Of 
!~With 
200  grams 
of  BaH202 
at  ioo° 
2*1 
3-6 
3 '4 
tt 
tt 
at  1200 
*'3 
47 
4*3 
« 
tt 
tt 
at  1500 
3'« 
5-0 
tt 
300  grams 
tt 
at  1800 
4*0 
io'8 
8*0 
u 
(< 
tt 
at  2000 
3*95 
II'O 
8-6 
tt 
600  grams 
tt 
at  1800 
3*79 
11*2 
18-2 
tt 
tt 
at  2500 
4-41 
12-5 
24*2 
Acetic  Acid. — The  proportion  of  this  acid  is  always  relatively  small; 
it  varies  with  the  temperature  and  the  proportion  of  the  baryta,  as  in 
the  previous  instances,  the  smallest  quantity  obtained  being  2*7  per 
cent.,  and  the  greatest  5*4  per  cent. 
Fixed  Residue. — The  total  weight  of  this  residue,  obtained  as  above 
mentioned  (including  6*53  per  cent,  of  organic  matter  carried  down  by 
the  barium  carbonate),  amounted  in  one  experiment  to  95*83  per  cent., 
and  in  another  to  96*5  per  cent,  of  the  albumin  used.  It  is  evident, 
therefore,  that  the  decomposition  under  the  influence  of  baryta  is 
accompanied  by  a  fixation  of  the  elements  of  water,  inasmuch  as  the 
separate  weights  of  the  components  b^ing  added  together  there  is  always 
an  excess  varying  from  10  to  14  per  cent.  The  ultimate  analyses  of 
the  fixed  residue  gave  very  constant  numbers,  which  did  not  vary 
greatly  even  under  different  formative  conditions,  the  mean  numbers 
being  C=48- 16;  H=8'2;  N=ii*03;  0=3075  percent. 
