3 i4 THE POPULAR SCIENCE MONTHLY. 



exasperating mental emotions. For it is a curious and not quite 

 explained but incontestable fact that a short fit of anger is often 

 enough not only to derange but to completely arrest the digestive pro- 

 cess for a whole day. Close behind the stomach is a group of ganglia, 

 the solar plexus, which sends out a large number of nerve-filaments 

 that communicate with the brain, and thus suggest the physiological 

 explanation of the curious phenomenon, though its final or teleologi- 

 cal purpose is somewhat less apparent. Haller connects it with the 

 fact that anger vitiates the saliva {teste, the virulent bite of enraged 

 animals), and suggests that by a wise arrangement of Nature the sus- 

 pension of the assimilative process may preserve the chyle from the 

 contamination of malignant humors ; and, in connection with the same 

 subject, Camper mentions the circumstance that fear often acts as a 

 sudden cathartic, perhaps for the purpose of easing the stomach, and 

 thus preparing the body for emergencies the necessity of flight, for 

 instance. Speculations of that sort lead to a field of curious but rather 

 recondite biological metaphysics ; but the empirical fact remains, and 

 partly suggests the rationale of another fact namely, that pleasurable 

 mental emotions act as a benignant digestive tonic. Hence, perhaps, 

 the peptic beatitude of " jolly paunches," fellows who seem constitu- 

 tionally unable to see the gloomy side of earthly concernments, and 

 wax fat on the prescription of Democritus, "Ride, si sapis." The au- 

 tocrat of the dinner-table should, therefore, peremptorily exclude all 

 conversational topics of an irritating character, as well as all business- 

 talk. A remarkable influence on the action of the bowels can be ex- 

 erted by mechanical laughter I mean, the agitation of the diaphragm 

 by means of a forcible and long-continued chuckle. Laurence Sterne 

 mentions that he was able to keep up this factitious kind of laughter 

 for minutes together, with or without the association of risible ideas. 

 On solitary evenings that talent could be utilized as a physiological 

 compensation for the absence of merry friends. 



For the effects of mental worry, and nervousness (often the after- 

 effect of stimulating medication), the best remedy, next to out-door 

 work, is a liberal alloicance of sleep ; and metropolitans who can not 

 afford to join the summer exodus should at least remove their beds to 

 a suburban cottage, far from the sleep-murdering noise of the busi- 

 ness centers. 



But neither long sleep nor short meals can save dyspeptics who 

 will insist on swallowing their food smoking hot. The walls of the 

 stomach are lined with a nerve-interwoven delicate membrane, which 

 suffers from scalding fluids as much as any other tegumental tissues 

 of the body, and by daily torrefactions becomes cither callous or 

 chronically inflamed, and in either case less fit for the performance of 

 its important functions. Our forefathers served their viands steam- 

 ing hot, but stuck at least to cool drinks, but hot French soups were 

 soon followed by hot tea and hot coffee. The " second breakfast," as 



