558 
Insects  Destructive  to  Books. 
<  Am.  Jour.  Pharm. 
(   December,  1910. 
life  that  has  been  conveyed  to  it  by  the  uncleanliness  in  preparing 
the  leather,  not  including  the  hundreds  of  substances,  many  of  them 
poisons,  especially  tannic  acid,  used  by  the  tanners  for  tanning 
purposes,  which  are  also  attractive  to  other  species  of  insects.  And 
just  as  the  animals  which  eat  the  plants  containing  various  chemical 
elements  thus  become  impregnated  with  acids,  so  will  the  insects  liv- 
ing upon  animals  and  plants  be  found  to  have  acids  in  their  com- 
positions. 
The  leather  is  destroyed  by  a  number  of  species  of  beetles,  such 
as  Lasio derma  serricorne,  Attageniis  pice  us,  Derm  estes  lardarius, 
and  Anthrenus  scrophularice. 
Wood  Bindings. — The  beetles,  Anobium  hirtum  and  Ptilinus 
scrricornis,  are  found  making  galleries  in  the  wooden  covers  of 
books. 
Poisons  Used,  Mineral, — We  have  in  the  minerals  of  the  earth 
many  poisons,  one  of  which,  arsenic,  is  of  especial  interest,  as  it 
has  been  the  established  rule  of  the  wall  paper  manufacturers  to  use 
it  in  large  quantities  ;  and  this  poison  is  one  that  attracts  various 
species  of  insects  on  account  of  its  medicinal  value.  Just  as  human 
beings  take  poisons  in  proportionate  ratio  to  the  needs  of  their 
systems,  and  especially  arsenic,  for  their  health,  so  do  the  insects  and 
lower  forms  of  life,  which  have  an  instinct  beyond  the  ordinary 
comprehension,  need  it ;  and  they  find  it  in  the  wall  papers  and 
colored  illustrations  printed  on  the  bindings  and  in  books.  Where 
sulphur  is  used,  other  species  will  be  attracted,  and  so  on  with  the 
various  poisons  which  are  used  in  the  arts.  The  "  bed-bug  "  also 
finds  food  in  the  poisons  used,  such  as  arsenic,  Paris  green,  etc.  The 
idea  that  this  insect  is  found  only  where  uncleanliness  prevails  has 
long  since  been  rejected,  as  it  is  constantly  found  where  absolute 
cleanliness  prevails. 
Flies  will  cling  to  wall  paper,  especially  in  damp  weather.  This 
is  due  to  the  moisture  in  the  atmosphere  causing  the  poisons  in  the 
paper,  which  flies  are  primarily  after,  to  become  soft  enough  for 
them  to  eat. 
Gases  ;  from  Heat. — It  is  accepted  as  a  fact  by  scientists  to-day 
that  the  nature  and  character  of  life,  in  the  material  sense  of  evolu- 
tion, has  for  its  base  the  heat  generated  by  the  physical  sun,  assisted 
by  the  moisture  of  the  atmosphere,  and  the  darkened  chambers  of 
the  earth,  which  are  necessary  in  the  first  stages  of  all  life  produc- 
tion.   Books  in  a  very  dry  and  warm  location  will  be  found  to  be 
