OP THE MICROSCOPE, 97 



The first point to be decided, is the kind of microscope that 

 should be procured that is to say, whether a simple or a com- 

 pound microscope is wanted. If the student is desirous of 

 working on objects^ under the microscope making dissections 

 of flowers, etc. a simple microscope, of any of the kinds de- 

 scribed in a previous chapter, will suit his purpose best. It 

 should be arranged on a stand, and this he can either do him- 

 self, or he can procure one of the many dissecting microscopes 

 which he will find described in the catalogues of the manufac- 

 turers. For such purposes a simple microscope is indispensa- 

 ble, though when we come to examine the results of our work, 

 (dissections, etc.) a good compound microscope is equally 

 necessary. 



Attempts have been made to combine these two forms of the 

 microscope in one instrument, and with considerable success, 

 so far as increasing our power to examine our work as it pro- 

 gresses is concerned. This is accomplished by so arranging 

 the simple microscope that a compound body with its eye- 

 piece may be slipped on or off, as required. And by using a 

 single concave lens as an eye-piece, we can secure considerable 

 magnifying power and great working distance, while at the 

 same time the object is seen erect and not inverted, as when 

 the ordinary compound body is used. This form is called the 

 "Brucke Loupe" and is too little known in this country. 

 But no such makeshift can take the place of a good compound 

 microscope, although it may form a useful and convenient ad- 

 dition to the student's outfit. 



The selection of a compound microscope will frequently be 

 determined, not only by the wants, but by the means of the 

 purchaser. To those who are obliged to put up with a cheap 

 microscope, the only advice that we can give is to get the best 

 they can for the money, and as newer and better microscopes 

 are constantly coming into market, the best thing the student 

 can do is to procure the latest catalogues of the different 

 dealers, and examine and compare what they have to offer. 

 There is no microscope in market to-day that will not probably 

 be excelled by something better in less than twelve months 

 from this time. 



To those whose means enable them to procure whatever they 



