26 THE BIOLOGICAL LITERATURE 



contain sketches of specialized pieces designed for petroleum testing 

 that could be used for biological experiments. The exchange of ideas 

 among the various sciences as a result of reading catalogues and adver- 

 tisements is probably more important than many people realize. 



The successful biologist depends upon a variety of sources of infor- 

 mation. One of his most valuable tools is the kind of library provided by 

 a university, and one of the most valuable techniques he can learn is to 

 use the library effectively. 



Reprints 



When a scientific periodical is printed, extra copies of each paper are 

 usually run off. These are not bound with other papers, but are given 

 or sold to the authors. These separate copies, or "reprints," are printed 

 from the same plates, and therefore are identical to the published paper. 

 The author distributes these reprints to persons he thinks would be 

 interested or to other scientists who request them. Anyone working on 

 cellular metabolism could request reprints from other writers on the 

 subject and thus could have his own collection of papers for careful 

 study. In turn, he provides reprints of his own papers to the other work- 

 ers. Sometimes it is easier to obtain a reprint from an author than to 

 obtain the journal in which the paper was published. 



Record systems 



Since the literature is voluminous— every year we read or become 

 aware of a vast number of papers pertaining to our work— some system 

 of listing these papers is essential. Most such record systems consist of 

 filing cards of one sort or another. 



Each researcher must develop his own system for keeping track of 

 the literature. For cards to be useful, there should be at least one card 

 for each paper, and that card should give authors; title; citation to 

 journal, volume, year, and pages; and preferably a brief summary of 

 contents. The information on the cards is useless unless it can be recov- 

 ered when needed. 



It must not he thought that some system is effortless; any system 

 requires expense and work. Elaborate cross-references become necessary 

 if the file of cards is large. You might choose to file the cards alphabeti- 



