254 
ON  THE  USE  OP  COFFEE  AS  A  BEVERAGE,  ETC. 
THE  USE  OF  COFFEE  AS  A  BEVERAGE  CONSIDERED  IN  A 
CHEMICAL  AND  PHYSIOLOGICAL  POINT  OF  VIEW. 
By  Professor  Lehmann. 
In  the  experimental  consideration  of  this  subject  the  author 
has  adopted  as  a  principle,  that  under  a  well  regulated  and  uni- 
form diet  and  mode  of  life,  the  quantitative  relations  of  the  sub- 
stances excreted  in  the  urine,  present  a  trustworthy  view  of  the 
general  assimilative  process  in  the  individual. 
He  has  therefore  selected  patients  whom  he  considered  fit,  and 
while  administering  to  them  either  coffee  or  its  various  constitu- 
ents separately,  has  made  such  regular  observations  of  the  urinal 
excretions  as  would  enable  him  to  infer  what  is  the  nature  of  the 
efficacy  of  coffee  and  of  its  constituents  respectively. 
In  determining  the  amount  of  urea,  he  has  adopted  the  method 
recently  put  forward  by  Liebig. 
The  general  results  of  his  investigation  are  : 
1.  That  a  decoction  of  coffee  exercises  two  principal  actions 
upon  the  organism,  which  are  very  diverse  in  character,  viz., 
increasing  the  activity  of  the  vascular  and  nervous  system,  while 
at  the  same  time  it  retards  the  metamorphosis  of  plastic  consti- 
tuents. 
2.  That  the  influence  of  coffee  upon  the  vascular  and  nervous 
system,  its  re-invigorating  action,  and  the  production  of  a  gen- 
eral sense  of  cheerfulness  and  animation  is  attributable  solely  to 
the  mutual  modification  in  the  specific  action  of  the  empyreu- 
matic  oil  and  the  caffeine  contained  in  it. 
3.  That  the  retardation  of  the  assimilative  process  brought 
about  by  the  use  of  coffee,  is  owing  chiefly  to  the  empyreumatic 
oil,  and  is  caused  by  caffeine  only  when  taken  in  large  quantity. 
4.  That  increased  action  of  the  heart,  trembling,  headache,  &c, 
are  effects  of  the  caffeine. . 
5.  That  the  increased  activity  of  the  kidneys,  relaxation  of  the 
bowels,  and  an  increased  vigor  of  mental  faculties,  passing  into 
congestion,  restlessness,  and  inability  to  sleep,  are  effects  of  the 
empyreumatic  oil. 
Professor  Lehmann  considers  it  therefore  necessary  to  regard 
the  action  of  coffee,  and  in  a  less  degree  that  of  tea,  cocoa,  alcohol, 
&c,  upon  the  organism,  as  constituting  an  exception  to  the  gen- 
