242 Dr Fuster on the Diseases of France 



It is, above all, from the association of the temperature with 

 other determinate conditions, that the prevailing diseases arise. 

 These conditions principally are, — the climate, the sun, the 

 winds, the waters, the aspects, the agricultural productions, 

 light, electricity, magnetism, fcc. 



Independently of these peculiar characters, under the influ- 

 ence of the conditions enumerated, the characters of the sea- 

 sons also react on each other, in so far as each of them trans- 

 mits emanations of its influence to the season which precedes 

 it ; in the same manner as each inherits, in its tium, and in 

 difi^erent degrees, the action of the season which has past. 

 This modifying influence, marked by certain observers, had 

 not, however, sufficiently attracted attention. M. Fuster has 

 set this truth in its clearest light ; he has, so to speak, fixed 

 the theory, established the doctrine of it. He has shewn that, 

 in this point of view, the principal characters of the seasons 

 are mingled, and grow together at the commencement and end 

 of their course, by the reciprocal penetration of their prevail- 

 ing qualities. This intimate fusion produces a mixed atmo- 

 spherical constitution, which participates at once of the cha- 

 racters of both seasons. Consequently a middle or mixed 

 atmospherical constitution opens and closes the march of each 

 season. 



Besides, we may remark here, as to the seasons in particu- 

 lar, that nothing is abruptly, and with precision, divided in 

 nature ; she almost always proceeds in the way of provident 

 transitions. 



The two elementary seasons do not contribute equally to 

 this mean constitution. The relations of their relative pre- 

 ponderance acknowledge also certain general laws, the formu- 

 las of which M. Fuster gives, but which it would be too tedi- 

 ous to develop here. 



What the author advances concerning the seasons, he ap- 

 plies equally to climates or regions. He assigns to them also 

 proper characters, and chax'acters transmitted by the diff^erent 

 relations between the neighbouring climates. A capital diff^e- 

 rence distinguishes the climates and the seasons ; — it is, that 

 the climates are fixed, while the seasons are transitory. 



M. Fuster has reasoned hitherto on the supposition, that the 



