78 TEE POPULAR SCIENCE MONT ELY. 



tion. It is most important that solid food should be duly prepared, 

 by chewing, for the action of the stomach ; and it is also important 

 that the starchy elements of food be sufficiently submitted to the 

 action of pure saliva. 



There are numerous other causes which affect the digestive organs 

 less directly, but no less injuriously. It has been assumed by some 

 writers that the conditions of civilization are incompatible with the 

 highest degree of health. But there is every reason to believe that 

 dyspepsia affects all races. The Laplander is especially subject to 

 water-brash ; the Maories of New Zealand suffer much from dyspepsia ; 

 and the use of bitter substances to promote digestion is known to 

 many savage tribes. The extremes of abstinence and repletion com- 

 mon with savages, their precarious mode of existence, their fits of 

 complete indolence, followed by exhausting fatigue, must cause them 

 a full share of digestive trouble. 



The relative superiority in physical strength of civilized over sav- 

 age nations has been sufficiently proved. Refined and settled habits 

 are not necessarily attended by any physical disadvantages. But it 

 is observable that those who live in towns are most affected by dys- 

 pepsia. There it is that the mental powers are most overtasked ; and 

 the relation between mind and body, as well as their mutual reactions, 

 disregarded or forgotten. Too large a share of the nervous energy, 

 so necessary for digestion, is expended in mental toil or business 

 anxieties. In many cases, attention to the commonest physical wants 

 is neglected in monotonous pursuits ; the appetite for food is disre- 

 garded until it no longer exists ; exercise is either not taken at all, or 

 is fitful and unseasonable ; ventilation is neglected, and a close and 

 polluted atmosphei-e is breathed. Such is no overdrawn picture of the 

 town life of vast numbers who suffer, more or less, from dyspepsia. 



Two habits, smoking and taking snuff, require special notice as 

 causes of dyspepsia. Excessive smoking produces a depressed condi- 

 tion of the system, and a great waste of saliva if the habit of spitting 

 is encouraged. I have met some severe cases of dyspepsia clearly re- 

 sulting from these causes. Some individuals.are unable to acquire the 

 habit of smoking even moderately. Deadly paleness, nausea, vomiting, 

 intermittency of pulse, with great depression of the circulation, come 

 on whenever it is attempted. But this incapacity is exceptional, and 

 so universal is the desire for tobacco, that it seems as if some want of 

 the system is supplied by its use. Smoking has been attacked and 

 defended with much zeal. Its adversaries have strongly urged that 

 the practice is a potent cause of dyspepsia. The late Sir Benjamin 

 Brodie was a great enemy to tobacco. But, as one of his biographers 

 has observed, he appeared in this instance to have departed from the 

 rule by which he was generally guided, to weigh impartially all the 

 facts bearing on an argument. Other names of eminence might be 

 cited in the ranks of those who aie strong opponents of smoking. On 



