ZA) A) NAGE NS 
INTRODUCTION. 
I. DEFINITION OF BIOLOGY AND ZOOLOGY. 
ALL natural objects may be roughly divided into three groups 
constituting the so - called Mineral, Animal, and Végetable 
kingdoms. The objects comprised in the mineral kingdom are 
all devoid of life, and they exhibit the following characters : 
a. Their chemical: composition is simple. They consist of 
either a single element, as is the case, for instance, with native 
gold; or, if combined, they almost always occur in nature in the 
form of simple compounds, composed of no more than two or 
three elements—as, for example, common salt, limestone, plas- 
ter of Paris, and many others. &. Mineral bodies are, when 
unmixed, composed of similar particles, which have no definite 
relations to one another, or, in other words, they are ommo- 
geneous. c. The form of mineral bodies is either altogether 
indefinite, when they are said to be “amorphous;” or, if they 
have a definite shape, they are crystalline, in which case they 
are usually bounded by plane surfaces and straight lines. d. 
When mineral bodies increase in size, as crystals may do, the 
increase is produced simply by the addition of particles from 
the outside (technically called “ accretion”). ¢. Mineral bodies 
exhibit no phenomena which are not purely physical and chem- 
ical, and they show no tendency to periodic changes of any 
kind. 
All the bodies which exhibit these characteristics properly 
belong to the mineral kingdom, and fall to be treated of by the 
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