INTRODUCTION. Ill 



perfect in itself made up of solids and fluids, and possess- 

 ing certain attributes, namely, a constant circulation of its 

 fluid parts, a constant appropriation of food and rejection of 

 waste matters growth thereby to a certain definite form, 

 and in many a definite size, together with the production of 

 germs, capable, under certain conditions, of producing beings 

 exactly similar to themselves. This constitutes organic life, 

 and is possessed by all vegetables. Animal life is exactly 

 the same, with the super-addition of will or mind in its 

 most perfect state, of instinct or some analogous function 

 in its lower states, or in quite the lowest a chemical and 

 mechanical difference only, such as shall determine the 

 choice of food and mode of assimilating it. This difference 

 consists in the vegetable feeding upon inorganic food, and 

 the animal on food which has received the stamp of organi- 

 sation. Creatures possessing life, whether vegetable or animal, 

 are called organisms. It is found that these organisms are 

 made up of certain atoms united in larger multiples than in 

 inorganic substances, which are either simple or compounded 

 of but few atoms ; thus water is composed (every atom 

 of it) of one atom oxygen, united to one of hydrogen. Com- 

 mon salt (every atom of it) is composed of one atom of the 

 metal sodium with one atom of chlorine. Chalk is com- 

 pounded of one atom of calcium in union with one of oxygen, 

 and this united to one atom of carbonic acid, itself composed of 

 one atom of carbon with two of oxygen. But organic com- 

 pounds are often made up of four or six elements, united in 

 multiples of their usual combining quantities. Thus, grape- 

 sugar is made up (every atom of it) of 24 atoms of carbon, 

 28 of hydrogen and 28 of oxygen ; these 78 atoms unite 

 and form one compound atom, of which the sugar is wholly 

 compounded, and thus, from such a complex nature, it 

 happens that most organic compounds are decomposed by even 

 a moderate degree of heat all by a heat equal to red-hot iron. 

 From these facts, it may be therefore stated, that all 

 organisms are complete in themselves, have definite lives or 

 existences, appropriate certain matters to themselves, grow 

 thereby, and are compounded of organic atoms. 



