To properly attach an objective is not always simple 

 and can not be done too carefully. One danger lies in 

 the fact that the objective may be dropped onto the 

 object and thus injure or destroy one or the other or 

 both, and another that the threads may be started wrong 

 by holding the objective sideways and the threads 

 injured. 



In this connection we draw particular attention 

 again to the convenience of the double, triple and 

 quadruple nose-pieces. The convenience which is 

 obtained from their use, freedom from danger to objec- 

 tives and saving of time, commend them in all cases 

 where two or more objectives are used. 



Finding an Object. The slide upon which the 

 object is mounted is placed upon the front of the stage 

 and slipped under the two spring clips to a point 

 where the object comes as nearly as possible in the 

 center of the opening of the stage. The slide should 

 pass easily under the clips, which, however, is not 

 the case when the forward ends of the clips are 

 too bluntly rounded or when they are too stiff. In 

 either case the clips may be bent so that the slide will 

 work easily. Some persons prefer to work without 

 clips, but this can only be done after considerable 

 experience has been acquired and only when the instru- 

 ment is in an upright position. 



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