Am.  Jour.  Pharrn.  \ 
June,  1904.  J 
Progress  in  Pharmacy. 
291 
Stearic  anilide  is  soluble  in  ether,  alcohol,  chloroform,  benzine, 
benzol  and  carbon  disulphide.    [Apothek.  Zeitg.,  1904,  page  234.) 
A  Differential  Test  for  Phenacetin  and  Acetaniliei  is  given  by  Et. 
Barral  (Jour,  de  Phar.  et  de  Chemie,  1904,  page  237),  as  follows: 
A  solution  of  phosphomolybdic  acid  added  to  an  aqueous  solution 
of  acetanilid  gives  a  yellow  precipitate,  which  does  not  dissolve  on 
heating.  The  same  reagent  added  to  a  solution  of  acetanilid  gives 
a  bright  yellow  precipitate,  which  is  readily  dissolved  again  on 
heating. 
Mandelin's  reagent — ammonium  vanadate,  1  ;  sulphuric  acid,  200 
— produces  a  bright  red  color  in  a  solution  of  acetanilid  that  is 
rapidly  changed  to  a  greenish  brown.  In  a  solution  of  phenacetin 
the  same  reagent  produces  an  olive-green  color  that  on  heating  is 
changed  to  brown  and  ultimately  black. 
The  Inclusion  and  Occlusion  of  Solvent  in  Crystals  has  been  investi- 
gated by  Theodore  William  Richards  {Proc.  Am.  Phil.  Soc,  T903, 
page  28), 'who  advances  this  as  one  of  the  most  frequent  as  well  as 
one  of  the  most  insidious  sources  of  error  in  quantitative  chemical 
investigations. 
Mr.  Richards  recounts  several  experiments  that  would  appear  to 
indicate  the  prevalence  and  magnitude  of  the  possible  inaccuracy 
from  the  unexpected  included  mother  liquor  and  also  demonstrate 
the  difficulty  of  eliminating  the  mother  liquor  by  ordinary  means. 
This  occluded  solvent  is  distinct  from  the  water  of  crystallization 
and  is  even  more  difficult  to  eliminate  than  the  latter* 
It  is  for  this  reason  that  Mr.  Richards  believes  it  to  be  practically 
impossible  to  determine  with  the  exactness  demanded  in  the  most 
accurate  work,  the  true  weight  of  any  salt  containing  water  of 
crystallization. 
The  N-rays  discovered  by  a  French  physicist,  M.  Blondlot, 
nearly  a  year  ago,  have  been  attracting  considerable  attention  dur- 
ing the  past  few  months.  This  is  largely  due  to  the  work  that  has 
been  done  in  France  by  Charpentier,  Blondlot  and  others. 
N-rays  appear  to  be  a  form  of  radiation  quite  distinct  from  the 
Roentgen,  or  X-rays ;  they  do  not  affect  photographic  plates 
directly,  but  do  have  the  property  of  increasing  the  luminosity  of 
phosphorescent  bodies,  like  sulphid  of  calcium. 
The  sources  of  N-rays  are  numerous  and  new  ones  are  constantly 
being  discovered.    It  has  been  found  that  they  are  emitted  by  a 
