Fee The Microscope in the Examination of Rocks. {January, i 
with each other that one even by aid of the magnifying glass 
cannot recognize them. 
A compound rock of such minute structure may appear to be 
a homogeneous one, as the individuality of its minerals is lost, in 
comparison with the whole appearance of the rock. The chemi- 
cal analysis of the compound will not furnish an adequate repre- 
sentation of its mineralogical composition, but will only give 
some figures of its elements, after which we classify the rock 
under examination by comparison with a group of rocks, with 
which it has the greatest resemblance in its chemical composition, 
At the same time we have to remember that there are rocks which 
are of the samt chemical composition, and yet their mineralogical 
constituents are different from each other. True, chemical in- 
vestigation has helped us to gain some valuable points according to 
which we may form some idea of the composing minerals, but not 
of their physical qualities, z. e., in which state of molecular arrange- 
ment they may be, and how they adhere to each other: 
Chemical analysis is therefore not a complete survey of the litho- 
logical nature of the rock; the task laid upon chemistry by 
lithology was too heavy, as the former destroys the architecture 
of our mineral aggregate, instead of examining it, We should 
therefore not wonder that this result of chemical investigation 
could not be used as a firm basis for lithology and geology. 
A great number of rocks, mineralogically different from each 
other, were treated and named according to their chemical compo- 
sition as one kind of rock, whilst lithology on the other hand 
unnecessarily enriched its nomenclature by giving to one and the 
same rock (the structure of which presented itself in various 
forms) different names, 
The study of palzontology without the aid of the microscope 
was limited, as it could only treat, in its description, of facts 
visible to the eye. We know by experience that nature by the 
process of petrifaction has not only preserved the macroscopical 
forms and organs of those fossil organisms, but also their micro- 
scopical one. These minute remains whether only organs of a 
macroscopical fossil or an organism by itself, rightly deserve to 
be studied with the same industry and endurance, with which 
their larger fellow organisms are favored ; the more, as we know 
that the microscopic organic. world takes and has taken an 
important position as architects of the sedimentary rock of our 
earth. The researches of the palzontologist enable him to meet 
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