im 



METEOROLOGY. — GROWTH OF PLANTS. 



Temperature of Temperature 



summer. w autumn. 



Bordeaux 70® Fahiu 58" 



Frankfort, A. M- . 65 50 



Lausanne 65.2 49.7 



Paris 65.8 52.2 



Berlin 63.2 48.0 



London 62.9 51.3 



Cherbourg 61.9 54.4 



Temperature of 

 the hottest month 



73.3® F. very favorahl* 



66.0 



65.8 



66.2 



64.4 Wine scarcely drinkable 



64.1 Vice not cultivated. 



63.2 



In high latitudes the disappearance of vigorous vegetation in plants 

 day depend quite as much on intensity of winter colds as on insuf- 

 ficiency of summer heat. The equable climate of the equatorial re- 

 gions is therefore much better adapted than that of Europe to de- 

 termine the extreme limits of temperature between which vegetable 

 species of different kinds will attain to maturity. Thus it has been 

 found that the vine between the tropics is productive in temperatures 

 that vary from 69° F. to 79° or 80°. I shall terminate with a list of 

 the temperatures favorable to the particular vegetables in the success 

 of which man is more especially interested. 



^«Ttimiim. Miuimtuit. 



Pine-apple " 



Melon " 



Vanilla " 



Guaduas " 



The vine 79 



CotBse 79 



Anise 77 



Wheat 74(1) 



Barley 74 59 



Potatoes 75(1) 52 



Arachaca 75 49 



Flax 74 54 



Apple 72 59 



Oak 67 61 



Maximum. Minimum. 

 The cocoa, or chocolate bean 82® F. 73° F. 



Banana " 64 



Indigo " 71 



Sugar-cane " 71 



Cocoa-nut " 78 



Palm " 78 



Tobacco " 65 



Manihot " 72 



Cotton-tree " 67 



Maize " 50 



Haricots " 59 



OrchU " 72 



Rice " 75 



Calabash " 72 



rjaricapapaya " 66 



^ IV. COOLING THROUGH THE NIGHT ; DEW, RAIN. 



When the sky is clear and calm during the night, vegetables cooi 

 down and very soon show a temperature inferior to that of the air 

 which surrounds them. This property of cooling in such circum- 

 stances belongs to all bodies ; but all do not possess it to the same 

 degree. Organic substances, for instance, such as wool or cotton, 

 feathers, &c., radiate powerfully and sink low ; polished metals, on 

 the contrary, have a very weak emissive or radiating power ; and 

 air and the gases in general radiate still more feebly. 



Inasmuch as a body is continually emitting heat, its temperature 

 can only remain stationary so long as it receives from surrounding 

 objects at every instant a quantity of caloric precisely equal in quan- 

 tity to that which it loses from its surface. 



From the moment that these incessant exchanges cease to be i: 

 a state of perfect equality, the temperature of a body varies ; it may 

 even experience a considerable degree of cooling if it is exposed 

 during a clear night in an open spot. In such circumstances, a body 

 gives off towards all the visible parts of the heavens more heat than 

 P wceives ; for the higher regions of the atmosphere are excessive* 



