108  Notes  on  Syrups.  {A  VaSfm™' 
of  the  bacterial  biogen,  saturating  the  receptors,- and  leading  to  the 
overproduction  of  bacterial 
R<T 
groups.  A  circulus  viciosus  is  thus  established,  which  will  con- 
tinue until  either  the  i  or  the  T  obtains  the  upper  hand,  when  the 
circle  will  turn  in  the  other  direction,  one  or  the  other  cell  being 
killed. 
This  necessarily  fragmentary  exposition  will  suffice  to  show  the. 
general  nature  and  scope  of  the  side-chain  theory.  The  few  illustra- 
tive examples  will  make  clear  how  this  theory  can  furnish  satisfac- 
tory explanations  of  the  facts  now  known  to  us.  It  must  not  be 
forgotten,  however,  that  the  conceptions  upon  which  these  hypoth- 
eses are  based  are  as  purely  symbolical  as  is  the  hexagon  by 
which  we  represent  the  benzol  molecule. 
NOTES  ON  SYRUPS. 
By  Frederick  W.  Haussmann. 
The  phenomenon  of  caramelization  is  not  solely  confined  to  syrup 
iodide  of  iron.  Other  syrups,  as  well  as  saccharine  preparations 
containing  metallic  salts,  show  a  similar  effect  on  standing.  Syrup 
of  ferrous  bromide  is  an  illustration,  as  well  as  the  very  frequent 
experience,  that  syrups  containing  free  acids  gradually  turn  dark. 
Recently  the  writer  observed  that  caramelization  takes  place  in 
syrups  containing  salts  of  manganese  and  a  number  of  similar  illus- 
trations may  be  cited. 
The  question,  why  caramelization  does  not  take  place  immedi- 
ately upon  preparing  syrup  ferrous  iodide  directly  from  sugar,  may 
be  answered  that  it  will  take  place  if  the  syrup  is  heated  to  excess. 
Recent  researches  have  shown  that  metallic  salts  cause  inversion 
of  sugar  in  solution,  and  this  is  very  probably  the  cause  of  caramel- 
ization in  syrup  of  iodide  of  iron  and  other  saccharine  preparations. 
SYRUP  OF  THE  HYPOPHOSPHITES. 
Considerable  difficulty  is  occasionally  experienced  to  obtain  com- 
plete solution  of  the  calcium  hypophosphite  in  preparing  this  syrup. 
