POND-LIFE. 225 



to realize the truth of his own exclamation, that "he 

 was outdone after all." 



In studying the contrasts in nature, no more interest- 

 ing experiment can be made than taking a drop of water 

 and placing it in the live-box, and then viewing it with 

 a moderate power under the microscope with the aid of 

 the spot lens, an invaluable dark-ground illuminator, 

 having the light thrown on to the mirror from the flat 

 side of the bull's-eye lens ; and here let me remind you 

 that the thin edge of the flame of the lamp is that which 

 should always be used, when the petroleum, if it be the 

 best that is, what is called " water- white " will give a 

 pure white and steady light. 



It would have spread out my story far beyond its 

 limits were I to attempt to enter upon the manifold et 

 ceteras of the instrument or its management : that is 

 not my object here. When I began my microscopical 

 studies I had very little exterior aid ; I found the greatest 

 aid from close personal observation. I worked on, re- 

 membering the little song, " If at first you don't succeed, 

 try again," until I learned all I needed to know. I recom- 

 mend every beginner to provide himself with a copy of 

 Jabez Hogg's book on the microscope, if he would know 

 all that he will need to know on the history of the 

 instrument that has been so useful to the world during 

 the last quarter of a century. There he will find, in easy 

 and unscientific language, a work copiously illustrated, 

 all about the mechanical and optical principles in the 

 construction of the microscope, its lenses, illumination, 

 and apparatus, together with popular illustrations of the 

 marvels of the invisible world. Should that work be 

 beyond his reach, then the little book of the late Mr. 

 Wood, "The Common Objects of the Microscope," will give 

 him a wonderfully cheap shilling's worth of readable in- 



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