MEDICINAL EFFECTS. 263 



particularly that of the bowels. But coffee, by diminishing 

 the action of the skin, lessens also the heat of the body, 

 but increases the vis-a-tergo, and therefore the heart's 

 action and fulness of pulse, thus exciting the mucous 

 membranes. The conditions, therefore, under which 

 coffee may be used are different from those suited to the 

 use of tea, and under these circumstances better adapted 

 for use among the poor and feeble as a dietecal beverage. 

 But, besides accelerating the action of the bowels, and, 

 according to Liebig, aiding in the secretion of the bile, 

 it also invigorates to a very high degree the ganglionic 

 system of the brain, soothing the painful feeling of 

 fatigue and exhaustion, stimulating to renewed mental 

 exertion, for which reasons it always has been highly 

 appreciated by students and literary people generally. 

 The exhilarating and stimulating effect which coffee 

 has on the human organization is due chiefly to the 

 characteristic principles which it contains. It excites 

 the heart's action, and, as that organ is feeble in the 

 morning and the skin is active, it is best adapted for use 

 at the morning meal, its action upon the nervous system 

 being less exciting than that of tea. Very strong coffee, 

 however, produces sleeplessness in many persons when 

 taken at night, owing to its effects on the heart's action, 

 by retarding that full action of this organ, which is 

 natural at night, and so requisite to permit sound sleep, 

 while if only a light infusion be prepared and taken at 

 night, these effects are not likely to be experienced. 



In typhoid and other fevers its action is frequently 

 very prompt and efficacious, particularly in the early 

 stages before local complications set in. Dr. Guillasse, 

 of the French navy, in a recent paper on typhoid 

 fever, states that '* Coffee has given us unhoped- 

 for satisfaction, for, after having dispensed it, we found, 



