WORK WITH THE HIGHER " POWERS." 239 



beauties, to which that cf the shepherd boy is innocently 

 enough a stranger, and of the two, permit me to inquire 

 which would make the better rnicroscopist? 



As far as our auditor is concerned, we rest the issue 

 on its merits. 



A few years ago we purchased for a gentleman well 

 known in microscope circles, a wide apertured objective. 

 The party was 110 novice, but on the contrary a real 

 hard and close worker with the instrument; and fur- 

 thermore, the gentleman had formerly filled the chair 

 of microscopy in one of our most honored colleges. 

 After working with this glass for about one year, he 

 applied to me for instruction in the use of this instru- 

 ment, proposing to spend his vacation with me, and for 

 this purpose the author was delighted with the proposal 

 and the arrangement was consummated by unanimous 

 consent. Now the main point actuating my honored 

 pupil was this: He had used his glass considerably 

 enough to discover that there were conditions involved 

 that he could not control as he desired. Sometimes he 

 could see better than at others; sometimes the glass 

 would work good naturedly, and then again, at others, 

 it wouldn't work well. In the course of instruction 

 which followed, a slide of navicula rhomboides was se- 

 lected (this, by the way, was a diatom) and placed on 

 the stand for examination with the objective named. 

 In point of " difficulty" these shells would have been 

 regarded as average specimens. We then look some 

 little time to explain as well as we could the behavior 

 of the object glass when in and out of adjustment, as 



