COMMON OBJECTS WORTH EXAMINING. 295 



may be examined, and be interesting yet common and 

 abundant. The reader will soon cease to be a begin- 

 ner. He will before long become so interested in 

 some special class of Nature's handiwork that he will 

 leave all the others and devote himself to that one. 

 No single student can expect or hope to cultivate all 

 departments of njicroscopical science. The field is too 

 vast and life is too short. Most heartily would I 

 recommend the' beginner in the use of the microscope 

 to spend several years if necessary, in taking short ex- 

 cursions into as many different microscopical depart- 

 ments as possible, and then intelligently to make a 

 selection of some-one scientific field, of which there are 

 many, and make its cultivation the work and the rec- 

 reation of his leisure hours. The work will soon be- 

 come recreation, and the recreation willsoon result in 

 increased knowledge, not only to the student-worker 

 bui; to the scientific world at large. There can be no 

 better way of employing one's leisure hours than by 

 scientific work or even by scientific play. The illustri- 

 ous Leidy, one of the greatest of naturalists and inves- 

 tigators, says in his monograph on the fresh-waiter 

 Rhizopods of North America, "The study of natural 

 history in the leisure of my life, since I was fourteen 

 years of age, has been to me a constant source of hap- 

 piness, and my experience of it is such that, independ- 

 ently of its higher merits, I warmly recommend it as a 

 pastime, than which, I believe, no other can excel it. 

 At the same time, in observing the modes .of life of 

 those around me, it has been a matter of increasing 

 regret that so few, so very few, people give attention 

 to intellectual pursuits of any kind. In the incessant 

 and necessary struggle for bread, we repeatedly hear 



