CONTENTS. VJ 



CONVERSATION VIII. 



ON THE NATURALISATION OF PLANTS. 



Plants more affected by Change of Temperature than by Change of Air, 

 Moisture, or Soil. Habits of Foreign Plants. Directions for 

 transplanting delicate Plants from a wanner Climate. Ditto from a 

 colder Climate. Construction- of Hot-houses and Green-houses. 

 - 113 



CONVERSATION IX. 



ON THE ACTION OF THE ATMOSPHERE ON PLANTS. 



Temperature of the Atmosphere. Moisture. Fogs. Vapors. Wind.- 

 Elevation and Temperature at which different Trees will grow. 121 



CONVERSATION X. 



ON THE ACTION OF WATER ON PLANTS. 



Water a Vehicle of Food, dilutes Plants, is a Vehicle for the Convey- 

 ance of Air. River Water preferable to that of Lakes or Springs, 

 for watering Plants. Rich Manure of Stagnant Waters. Water- 

 ing Plants. The Seed when Germinating, when in Flower, when in 

 Fruit. Seeds when Ripening. Natural Means of Watering. 

 Rain. Dr. Well's Theory of Dew. Melted Snow. - 129 



CONVERSATION XI. 



ON THE ARTIFICIAL MODES OF WATERING PLANTS. 



Watering Pots applicable only to Garden Culture. Watering Green- 

 house Plants. Watering by Infiltration applicable to delicate Plants 

 and to Meadows. Watering by Irrigation. Meadows. Rice 

 Fields. The Pelagra. Draining Land. Pontine Marshes. 

 Marshes of Holland and of Tuscany. Valley of Chiana. - 139 



CONVERSATION XII. 



ON THE ACTION OF SOIL ON PLANTS. 



Origin of the Formation of Soil. Argillaceous Soil. Sandy Soil. 

 Sandy Deserts. Sand of Rivers. Steppes. Sand-Hills. Belgic 

 Cultivation. Campine. On the Improvement of Soil by Tillage. 

 Instruments of Agriculture. Of Ploughing. 150 



