^*ApXi8P84arm*}  So-called  Bismuth  Breath.  179 
tion  of  such  persistent  odor  that  for  the  remainder  of  the  session  the 
patient  had  to  sit  apart  from  his  fellow  students. 
The  experiments  ii\  this  direction  made  upon  several  friends,  and 
also  upon  myself  are  as  follows : 
Tellurous  oxide  (Te02)  was  prepared  by  treating  metallic  tellurium 
with  nitric  acid,  evaporating  to  dryness  and  igniting  the  product. 
Some  of  the  resulting  tellurous  oxide  was  taken  by  myself  in  doses  of 
0*005  gm.  each.  Three  doses  were  taken  on  May  8,  1883,  at  1,  4, 
and  7  o'clock  P.  M.  In  15  minutes  after  the  first  dose  the  breath  had 
a  strong  garlic-like  odor,  and  in  an  hour  a  metallic  taste  was  observed. 
An  hour  after  the  second  dose  the  urine  and  sweat  had  the  garlic-like 
odor,  which  was  also  observed  in  the  faeces  on  May  12.  The  metallic 
taste  was  observed  for  72  hours,  and  the  garlic-like  odor  in  the  urine 
for  382  hours,  in  the  sweat  for  452  hours,  in  the  faeces  for  79  days, 
and  in  the  breath  it  was  still  present,  though  very  faintly,  after  237 
days. 
In  order  to  determine  the  smallest  quantity  of  tellurous  oxide  which 
would  be  required  to  produce  the  garlic-like  odor  the  following  solu- 
tions were  made : 
I.  0*001  gm.  of  tellurous  oxide  was  dissolved  in  potassium  hydrate 
and  sufficient  distilled  water  to  obtain  100  cubic  centimeters.  5  cc. 
contain  0'00005  gm.  tellurous  oxide. 
II.  0*00025  gm.  of  tellurous  oxide  was  dissolved  with  the  aid  of  a 
little  hydrochloric  acid  in  sufficient  distilled  water  to  make  100  cc. 
5  cc.  are  equal  to  0*0000125  gm.  of  tellurous  oxide. 
III.  Made  like  the  preceding,  but  diluted  to  200  cc.  5  cc.  are  equal 
to  0*00000625  gm.  tellurous  oxide. 
IV.  0*0001  gm.  tellurous  oxide,  sufficient  hydrochloric  acid  and 
water  to  measure  100  cc.  5  cc.  are  equal  to  0*000005  gm.  tellurous 
oxide. 
V.  Like  the  preceding,  but  diluted  to  500  cc.  5  cc.  are  equal  to 
0*000001  gm.  tellurous  oxide. 
VI.  100  cc.  of  solution  V  was  diluted  with  100  cc.  of  distilled 
water;  each  cc.  represents  0*0000001  gm.  tellurous  oxide. 
These  solutions  were  given  to  a  number  of  young  men  ;  but  no  one 
was  experimented  upon  a  second  time. 
I.  After  one  dose  of  5  cc.  of  this  solution,  the  garlic  odor  became 
perceptible  in  the  breath  in  35  minutes  and  lasted  about  75  hours. 
II.  Three  doses  of  5  cc.  each  were  taken  after  three  succeeding 
