Am.  Jour.  Prjarrn. 
April,  1902. 
Spread  of  Tuberculosis. 
171 
number  found  in  any  specimen ;  and  many  of  the  specimens  under 
a  one-twelfth  oil  immersion  lens  showed  fields  of  bacilli  too  numer- 
ous to  be  counted. 
Among  other  findings  were  large  and  small  squamous  epithelium, 
and  occasionally  very  small  epithelial  cells  more  or  less  intimately 
connected  with  thick  mucus  and  leucocytes.  The  tubercle  bacilli 
were  commonly  associated  with  these  elements,  but  were  occasion- 
ally found  singly  or  a  number  of  bacilli  without  any  other  elements 
in  the  field. 
Conditions  Influencing  the  Spray. — From  patients  showing  tuber- 
cular laryngitis  and  from  those  who  talked  loudly,  or  who  were  fre- 
quently clearing  their  throats,  the  most  spray  was  found.  In 
patients  very  weak,  speaking  only  in  a  whisper,  scarcely  any  spray 
collected  on  the  slide,  and  this  seldom  contained  any  bacilli.  Men 
wearing  heavy  mustaches  ejected  no  spray  on  the  slide  until  after 
the  mustache  was  held  from  falling  over  the  mouth.  Coughing 
with  the  mouth  open  must  necessarily  favor  the  production  of  the 
spray.  The  detection  of  the  bacilli  in  these  fine  droplets  of  the 
spray  was  greatly  facilitated  by  the  use  of  a  low-power  lens  for  the 
purpose  ot  locating  such  droplets;  after  which  a  one-twelfth  oil-im- 
mersion lens  was  used.  Droplets  not  perceptible  to  the  naked  eye 
were  often  found  in  this  manner,  and  such  particles  not  infrequently 
contained  tubercle  bacilli,  and  at  times  in  great  numbers. 
Hygiene. — The  above  detailed  observations  prove  conclusively 
that  persons  suffering  from  consumption  are  constantly  contaminat- 
ing the  air  about  them  with  tubercle  bacilli,  which  are  perpetually 
emitted  in  connection  with  this  spray.  This  spray  may  remain  float- 
ing in  the  air  of  a  room  for  hours,  and  may  alight  on  the  furniture, 
carpets,  etc.,  but  whenever  agitated  it  rises  from  such  articles  in  the 
form  of  dust,  again  polluting  the  air  of  the  room.  Persons  entering 
the  room  of  a  consumptive  must,  therefore,  take  into  their  lungs 
with  each  inspiration  a  variable  number  of  tubercle  bacilli,  depend- 
ing entirely  upon  the  degree  of  contamination  of  the  air  in  that 
room.  If  the  person  breathes  with  the  mouth  open  the  bacilli  may 
enter  the  throat  and  be  swallowed.  In  this  manner  infection  takes 
place  through  the  alimentary  tract.  The  taking  of  food  is  liable  to 
excite  coughing  in  consumptives,  and  for  this  reason  it  is  indiscreet 
for  healthy  persons  to  dine  at  the  same  table  with  them,  for  the 
spray  collects  on  the  food  to  be  eaten  by  all. 
