628 
Varieties. 
j  Am.  .Jour.  I'harui. 
(      Dec,  1881. 
VAEIETIES. 
Hygiene  of  the  Teeth. — A  hard^crust  is  the  best  possible  dentifrice. 
I  never  could  get  myself  to  believe  in  the  natural  necessity  of  a  tooth- 
brush.    The  African  nations,  the  Hindoos,  the  natives  of  Southern 
Europe,  the  South  Sea  Islanders,  the  Arabs,  the  South  American  vegeta- 
rians, in  short,  three-fourths  of  our  fellow-men,  besides  our  next  relatives,, 
the  frugiverous  animals,  have  splendid  teeth  without  sozodont.    I  really 
believe  that  ours  decay  from  sheer  disuse ;  the  boarding-house  homo  lives 
chiefly  on  pap — wants  all  his  meats  soft-boiled,  and  growls  at  cold  biscuit  or 
an  underdone  potato ;  in  other  words,  he  delegates  to  the  cook  the  proper 
functions  of  his  teeth.    We  hear  occasionally  of  old  men  getting  a  second,, 
or  rather  third,  set  of  teeth.    I  met  one  of  them  in  northern  Guatemala, 
and  ascertained  that  he  iiad  become  toothless  during  a  twelve  years' 
sojourn  in  a  seaport  town,  and  that  he  got  his  new  set  upon  his  return  to 
his  native  village,  where"  circumstances  obliged  him  to  resume  the  hard 
corn-cake  diet  of  his  boyhood  years.    His  teeth  had  reappeared  as  soon  as 
their  services  were  called  for,  and  would  probably  never  have  absented 
themselves  if  a  pap-diet  had  not  made  them  superfluous.    An  artificial 
dentifrice  will  certainly  keej)  the  teeth  white,  but  that  does  not  prevent 
their  premature  decay ;  disuse  gradually  softens  their  substance,  till  oiie 
fine  day  the  hash-eater  snaps  his  best  incisor  upon  an  unexpected  piece  of 
bone.    Every  old  dentist  knows  hundreds  of  city  customers  whom  the 
daily  use  of  a  tooth-brush  did  not  save  from  the  necessity  of  applying, 
before  the  end  of  the  fortieth  year,  for  a  complete  "celluloid  set."    I  do 
not  say  that  a  soft  tooth-brush  and  such  dentifrices  as  oatmeal  or  burned 
arrow-root  can  do  any  harm,  but  for  sanitary  purposes  such  precautions 
must  be  supplemented  by  dental  exercise.    Let  a  child  invigorate  its  teeth 
by  chewing  a  hard  crust,  or,  better  yet,  a  handful  of  "  St.  John's  bread," 
or  carob-beans,  the  edible  pod  of  the  Mimosa  siliqua.   Children  and  whole 
tribes  of  the  northern  races  seem  to  feel  an  instinctive  desire  to  exercise 
their  teeth  upon  some  solid  substance,  as  pet  squirrels  will  gnaw  the  furni- 
ture if  you  give  them  nut-kernels  instead  of  nuts.  Thus  Kohl  tells  us  that 
the  natives  of  southern  Russia  are  addicted  to  the  practice  of  chewing  a 
vegetable  i^roduct  which  he  at  first  supposed  to  be  jiumpkin  or  melon 
seeds,  but  found  to  be  the  much  harder  seed  of  the  Turkish  sunflower 
(Helianthus  perennis).     Their  national  diet  consists  of  milk  kukuruz 
(hominy,  with  butter,  etc.),  and  boiled  mutton,  and  they  seem  to  feel  that 
their  Turkoman  jaws  need  something  more  substantial.    The  schoolboy 
habit  of  gnawing  penholders,  finger-nails,  etc.,  may  have  a  similar  signifi- 
cance.    The  Mimosa  siliqua  would  yield  abundantly  in  our  Southern 
States,  and  its  sweet  pods  would  make  an  excellent  substitute  for  chewing 
gum.     Our  practice  of  sipping  ice-cold  and  steaming-hot  drinks,  turn 
about,  has  also  a  very  injurious  effect  upon  the  brittle  substance  that  forms 
the  enamel  of  our  teeth ;  no  jDorcelain  glaze  would  stand  such  abuse  for 
any  length  of  time,  and  experience  has  taught  hunters  and  dog-fanciers 
that  it  destroys  even  the  bone-crushing  fangs  of  the  animal  from  which 
our  canine  teeth  derive  their  name. — Dr.  Felix  L.  Oswald,  in  Popular 
Science  Monthly  for  November. 
