146 THE LAWS OF ORGANIC 



bronchia and lungs, and particularly to dysen- 

 teric symptoms. These diseases, at this period 

 of the year, are so prevalent that they are 

 occasionally supposed to be contagious, an 

 idea by no means correct. That many indi- 

 viduals are affected with the same complaints 

 at this period cannot be called in question, but 

 the number is no proof whatever that these are 

 propagated by contagion. The universality of 

 the diseases is against the supposition, and con- 

 tributes much to show their non-contagious 

 nature. The causes which produce these affec- 

 tions are general, and the systems on which they 

 have to act are in similar circumstances. If one 

 individual be subject to dysentery or catarrh, 

 from the condition of the circulation constituting 

 a greater degree of susceptibility, it is reasonable 

 to suppose that a thousand may be similarly si- 

 tuated : they possess the same liability, except in 

 so far as this liability is modified by a difference 

 of dress, mode of living or pursuits, or original 

 constitution. The minute investigation of the sub- 

 ject does not strictly belong to this chapter, and 

 therefore we must be satisfied at present with its 

 general illustration. 



CLVIII. If the unexpected cold of winter 

 produces unfavourable results upon the system, 

 we perceive that the unusually warm days of 

 spring also occasion analogous effects. The sun, 

 that gives premature development to vegeta- 



