CHAPTER II 



THE MICROSCOPE 



PROBABLY the majority of readers of the present book will 

 already possess a microscope, and for these it will simply be 

 a question of adapting it in the best possible manner to the 

 requirements of photo-micrography. Others, however, will 

 prefer to purchase an instrument specially suited to the 

 work ; or, again, in those cases in which the study is being 

 taken up from the beginning, it will be useful to know some 

 of the points to be observed in the mechanical construction 

 of a microscope, so that a suitable selection may be made. 



Microscopes have not altered in general design for very 

 many years, and up to comparatively recent times there were 

 two well-defined types : the one generally known as the 

 English, and the other as the Continental, model. They differ 

 mainly in one particular the manner in which the body 

 part is supported. In the English models it is generally 

 supported on a tripod foot, which has a considerable spread. 

 The result is that the English model microscopes are usually 

 rigid and stable whether in a vertical, inclined, or horizontal 

 position. In the Continental models the body is supported 

 on one metal casting, which consists of a horse-shoe foot with 

 two vertical projections, and between these it can be swung, 

 a pin or rod passing through and allowing of its inclination 

 about this point as an axis. 



It is, perhaps, unfortunate that of late years the English 

 makers have possibly as the result of competition gone 

 towards the Continental model, at least in the cheaper type 

 of instruments. On the other hand, the Continental makers 

 have appreciated that the English design, in the matter of 



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