328 
Varieties. 
(  Am.  Jour.  Pharm. 
\       July,  1875. 
based  upon  the  physical  characters  of  mercury,  which  solidifies  at  a  very  low  tem- 
perature and  boils  at  a  very  high  temperature.  Mr.  Williams,  therefore,  takes  the 
Interval  between  these  two  points  and  divides  it  into  one  thousand  degrees,  making 
his  zero  the  solidifying  point  of  mercury.  According  to  this  scale  the  melting-point 
of  ice  is  100°  and  the  boiling-point  of  water  350°. 
Among  the  advantages  to  be  derived  from  such  a  scale  may  be  mentioned  the 
avoidance  effractions  of  degrees,  since  the  degrees  are  very  much  smaller  lhan  those 
of  either  the  Centigrade  or  Fahrenheit  scales.  Another  advantage  of  the  Milligrade 
Scale,  as  it  is  termed  by  Mr.  Williams,  is  the  doing  away  with  minus  degrees,  while 
at  the  same  time,  the  indication  of  temperatures  below  the  freezing-point  of  water  is 
sufficiently  distinct,  as  all  numbers  below  100°  of  the  Milligrade  Scale  are  between 
0°  and  — 40°  of  the  Centigrade  scale.  These  are  certainly  considerable  advantages, 
but  it  remains  to  be  seen  whether  they  are  sufficient  to  ensure  the  substitution  of  the 
Milligrade  Scale  for  those  now  in  common  use. — Pharm.  Journ.  and  Trans. y  May 
8th,  1875. 
Chlorofop.m.  By  C.  Remys, — (i.)  Pure  cholorform  has  a  specific  gravity  of 
i'5oo  at  15"^  C.  and  boils  at  6o'5^,  if  the  sp.  gr   be  the  boiling-point  is  5975° 
—  60°,  and  the  sample  contains  about  I  per  cent,  alcohol. 
(2.)  A  sample  of  higher  boiling-point  than  60-5°  contains  such  substances  as 
amyl  and  butyl  compounds;  the  sp.  gr.  of  such  a  sample  may  rise  to  1-502°. 
(3.)  The  presence  of  ^  per  cent,  of  alcohol  lowers  the  sp.  gr.  -002.  A  small 
quantity  of  alcohol  is  the  best  preservative  of  chloroform  against  decomposition. 
(4.)  Decomposition  of  chloroform  takes  place  even  in  the  dark.  The  smallest 
trace  of  moisture  and  air  sets  up  decomposition,  the  chief  products  being  chlorine, 
hydrochloric  acid  and  phosgene  gas. 
(5.)  All  commercial  chloroform  contains  fusel  oil. — Journ.  Chem.  Soc,  May, 
1875,  from  Arch.  Pharm.  [3],  v,  313-323. — 
KosiN.  By  F.  A,  Fliicklger  and  E.  Buri. — The  koso-tree  is  cultivated  in  every 
^'illage  in  Abyssinia,  and  its  female  flower  panicles  have  been  used  there  for  a 
long  time  as  a  domestic  remedy  against  tapeworm.  The  koso-flowers  yield  about 
3  per  cent,  of  kosin,  a  yellowish  crystalline  b  idy,  without  smell  or  taste,  and  to 
which  the  anthelmintic  properties  of  the  flowers  have  been  attributed.  The  specific 
gravity  of  kosin  is  so  high,  that  it  sinks  in  sulphuric  acid  of  sp.  gr  1-842.  It  is 
freely  soluble  in  ether,  benzin,  carbon  sulphide,  chloroform  and  boiling  alcohol. 
Aqueous  solutions  of  the  caustic  and  carbonated  alkalies  also  readily  dissolve  it, 
and  when  such  solutions  are  neutralized  the  kosin  is  precipitated.  Its  formula  is 
C31H35O10. — Journ.  Chem.  Soc,  May,  1875,  from  Pharm.  Journ.  Trans.  [3],  v,  562. 
Composition  of  Gum  Tragacanth. — GIraud  has  made  a  minute  examination 
of  the  chemical  characters  of  gum  tragacanth.  He  finds  (i)  that  this  gum  is  but 
very  slightly  soluble  in  water,  and  that  the  product  in  the  filtrate  is  not  a  definite 
principle  like  arabin,  but  is  a  mixture  of  several  substances;  (2)  that,  digested  on 
the  water-bath  for  twentj/^  four  hours,  with  fifty  times  its  weight  of  water,  much  of 
it  is  transformed  into  a  soluble  gum,  which  no  longer  swells  after  drying;  this  new 
substance  is  pectin  ;  (3)  that,  under  the  action  of  water  containing  i  per  cent,  of 
