Vm CONTENTS. 



Uses of the vital principle 40 



1. J'^3 relations to agriculture as a science . . . . .40 



2. Its relations to Natural Tlicology 41 



3. Moral effect of considering this power 43 



Sect. 2. Definitions. — Conditions necessary to develope the Vital 

 Prmciple in the seed, bulb and bud. 



Definitions — 1. Of eeed 43 



,2. Of cotyledons. 3. Radicle. 4. Plumala. 5. Bulbs. 6. Buds 44 

 7. Eyes. 8. Chemical transformations — catalytic force. 9. Of 



a simple substance ........ 45 



10. Of Compound bodies. 11. Of alkalies and acids. 12. Of 



salts. 13. Of equivalents. 14. Organic constituents . 46 



15. Inorganic constituents. ...,.:. 47 



Organic Constituents — 1. Oxygen 47 



2. Hydrogen — water 47 



3. Carbon, carbonic acid 48 



4. Nitrogen, nitric acid, ammonia 48 



Germination — Conditions of ....... 49 



1. Moisture — its influence upon germination . . . .49 



2. Air " « 50 



3. Heat « ".-... 51 



4. Light " " 52 



Changes during the process of germination . . . .53 



Methods of promoting germination. 



1. By immersing the seeds in hot water . . . .54 



2. Experiments by Mr. Bowie . . . . . .54 



3. By mixing seeds with substances which yield oxygen easily 55 

 Object of all the vegetable functions — propagation; effected by 



seeds, buds, bulbs and leaves ....... 55 



By cuttings, layers and suckers 56 



Theory of the formation of the different organs of plants . 57 



Sect. 3. Definitions — Conditions of the growth of plants. 



Definition 1. Of soil 57 



2. Of sub-soil 58 



Organs of nutrition — 1. Roots, different kinds of . . .58 



2. Stem or culm — its functions 58 



3. Leaves, their structure and office 59 



4. Flower leaves or petals — their office — analogy between ani- 



mal and vegetable bodies 60 



