MICROSCOPES. 



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to make a thing look bigger than it is, and to say you have 

 magnified it so many times. What we want is to use the 

 magnifying power that will show to the greatest advantage 

 each particular structure which we want to examine. You 

 should use the lowest power that will enable you to do that, 

 since it is often very important to see as much as possible of 

 the object, so as to understand the bearings of one part on the 

 other, and for this you must use low powers ; but when 

 you want to define certain very minute structures, you must 

 use high powers. You should always try first a low power 

 and see what that shows, and then examine with a higher 

 power in order to resolve structures that cannot be resolved with 

 lower powers ; but never use high powers unless there is some 

 evidence of such minute structure as cannot be properly seen 

 with low. 



