EDITORIAL. 
883 
Serpents  in  the  Dove's  Nest.  By  Rev.  John  Todd,  D.  D.  I.  Fashionable 
Murder.  II.  The  Cloud  with  the  Bark  Lining.  Boston  :  Lee  &  Shep- 
ard,  1867. 
This  pamphlet  bears  on  the  same  subject  as  the  foregoing,  considering 
the  crime  chiefly  in  a  religious  point  of  view.  We  wish  both  works  a  very 
wide  circulation,  so  that  they  might  be  read  by  "  every  woman." 
The  art  of  manufacturing  Soap  and  Candles,  including  the  most  recent  dis- 
coveries ;  embracing  all  kinds  of  ordinary  hard,  soft  and  toilet  soaps,  espe- 
cially those  made  by  the  cold  process  •  the  modes  of  detecting  frauds,  and 
the  making  of  tallow  and  composite  candles.  By  Adolph  Ott,  Ph.  I). 
Philadelphia,  Lindsay  &  Blakiston. 
This  is  a  neat  little  volume  of  nearly  two  hundred  pages,  aiming  chiefly 
at  practical  instruction.  The  wood-cuts  of  apparatus  are  very  well  exe- 
cuted, and  convey  a  clear  idea  of  their  intrinsic  parts.  The  instructions  for 
making  soap  and  candles  are  clear  and  concise,  and  we  think  will  furnish 
many  useful  hints  to  those  interested  in  that  industrial  branch.  From 
our  personal  knowledge  of  the  author,  we  expected,  however,  to  see  the 
chemical  portion  of  his  treatise  treated  with  more  regard  to  the  present 
actual  state  of  this  important  science.  The  paragraph  "  potassa,"  in 
chapter  ii.,  states:  "This  alkali  is  called  in  commerce  vegetable  alkali,  sal 
tartar,  pearlash,  potash,  and  hydrated  protoxide  of  potassium."  The  idea 
which  the  author  intended  to  convey  is  not  clearly  expressed  ;  for  he 
knows  very  well  that  under  the  above  names  potassa,  its  carbonates,  and 
mixtures  of  the  two  in  different  states  of  purity,  are  known.  The  com- 
mercial  "  concentrated  lye  "  that  we  are  acquainted  with  is  not  liquid,  as 
stated  on  page  40.  The  explanation  of  the  term  "  fat,"  on  page  57,  is 
scarcely  satisfactory,  nor  is  the  enumeration  of  margaric  acid  among  the 
common  fatty  acids  in  consonance  with  our  present  knowledge  of  the  fats : 
for  Heintz  has  long  since  shown  that  what  has  been  called  margaric  acid 
by  Chevreuland  afterwards,  is  a  mixture  of  stearic  and  palmitic  acids,  and 
this  latter,  though  present  in  most  animal  and  vegetable  fats,  is  not  named 
at  all  by  Mr.  Ott.  If  alcohol,  treated  with  one-half  of  50  grains  commercial 
soda,  leaves,  on  evaporation,  20  grains  of  caustic  soda,  the  commercial  arti- 
cle would  contain  80,  not  40  per  cent,  of  the  alkali.  Page  44  is  to  be 
corrected  by  reading  100  instead  of  50.  In  chapter  v.,  ««  valuemetry,"  the 
instructions  for  determining  the  amount  of  fat  are  not  clear  enough  ;  in- 
stead of  washing  the  fat  on  a  filter,  it  is  best  washed  by  repeated  fusion 
with  pure  water.  For  determining  the  amount  of  rosin  in  soap,  the  well 
known  approximate  methods  are  given  •  we  can  appreciate  the  difficulties 
to  be  contended  with  in  this  case,  having  ourselves  experimented  for  a 
lengthy  period  without  arriving  at  any  more  satisfactory  results.  For 
estimating  the  amount  of  alkali  in  soap,  the  reader  is  referred  to  the  chap- 
ter on  alkalimetry,  where  commercial  alkalies  only  are  treated  of. 
.  We  are  sure  that  in  a  new  edition  the  author  will  remedy  such  defects  ; 
in  the  meantime  we  commend  it  to  the  favorable  notice  of  those  interested. 
M. 
