CONTENTS. 



INTRODUCTION. 



GENERAL REMARKS ON THE INFLUENCE OF PHYSICAL AGENTS ON ORGANIZATION AND LIFE. 



Object of the Work stated. Connexion of Organization with the Imponderable Principles. Gen- 

 eral Laws direct all Astronomical Occurrences and Physical Events. Transitory Nature of all 

 Combinations, and especially those which are Organized. Time is an Element of Life. Inor- 

 ganic Changes are brought about by Physical Laws, as also is the Extinction of Living Races. 

 Influence of Climate on the Distribution and Character of Animals and Plants. Relations 

 between Animated Forms and the Atmosphere. Influence of Currents in the Air and in the Sea. 

 Gradual Emancipation of the Higher Races from the Direct Action of External Agents Page 1 



CHAPTER I. 



ON THE ACTION OF THE SUNBEAMS IN PRODUCING ORGANIZED BODIES. 



The Growth of Conferva; in Water. Production of Green Matter by Spun Glass and Inorganic 

 Bodies. It requires a Sporule, Cell, or Objective Germ. Mode of Diffusion of Gases into 

 Water. Influence of Temperature on the Process. Action of the Sun's Rays on these Gases. 

 Two Atmospheres around the Earth. Sources of Supply of the expended Gases. 



Application of these Principles to the Production of Chlorophyl in Leaves. The Digestion of 

 Plants . . . . . . . . . . . . . . .15 



CHAPTER II. 



ON THE MECHANICAL CAUSE OF THE FLOW OF THE SAP IN PLANTS. IT IS DUE TO THE CARBONIZATION 

 OF WATER IN THE LEAVES BY THE LIGHT OF THE SUN. 



The Flow of Sap and Circulation of Blood are probably due tothe same Physical Cause. Amount 

 of Water circulating in Plants. Botanical Theory of the Flow of Sap -fails for the descending 

 Sap. 



Capillary Attraction described. Elevation or Depression of Liquids depends on their wetting or 

 not wetting the Tube. No Flow in an ordinary Capillary Tube. Conditions for producing a 

 Flow such as Evaporation, Decomposition, and Solution. Endosmosis produced on these Prin- 

 ciples by Solution. Dutrochefs Experiments. Explanation of them. General Law of these 

 Movements. Force with which they take place. Capillary Attraction due to Electricity. 



Application of these Principles to the Ascent of the Sap. Exhausting Action of the Leaves. Cause 

 of the Descent of the Sap. 



The Light of the Sun is the Cause of the Flow of the Sap both in its Ascent and Descent . 22 



CHAPTER III. 



ON THE MECHANICAL CAUSE OF THE CIRCULATION OF THE BLOOD. 



Ancient Theory. Description of the Systemic, Pulmonary, and Portal Circulation. General Law 

 of Movement. Capillary Relations of Arterial and Venous Blood to the Tissues. The Systemic 

 Circulation is due to the Deoxydation of Arterial Blood, and its Direction is therefore from the 

 Artery to the Vein. 



Pulmonary Circulation. Capillary Relations of Arterial and Venous Blood to Atmospheric Oxy- 



