CH. X] LABELING AND CATALOGUING SLIDES 337 



mounting one may use Canada balsam or mount dry on a cell ( 504, 

 511). See Newcomer, Amer. Micr. Soc.'s Proc., 1886, p. 128; see 

 also E. H. Griffith and H. L. Smith, Amer. Jour, of Micros., iv, 102, 

 v, 87; Amer. Monthly Micr. Jour., i, 66, 107, 113; Cunningham, 

 The Microscope, viii, 1888, p. 237. 



LABELING, CATALOGUING AND STORING MICROSCOPIC PREPARATIONS 



524. Every person possessing a microscopic preparation is inter- 

 ested in its proper management; ' but it is especially to the teacher and 

 investigator that the labeling, cataloguing, and storing of microscopic 

 preparations are of importance. "To the investigator, his specimens 

 are the most precious of his possessions, for they contain the facts 

 which he tries to interpret, and they remain the same while his knowl- 

 edge, and hence his power of interpretation, increase. They thus 

 form the basis of further or more correct knowledge; but in order to 

 be safe guides for the student, teacher, or investigator, it seems to the 

 writer that every preparation should possess two things: viz. a label 

 and a catalogue or history. This catalogue should indicate all that 

 is known of a specimen at the time of its preparation, and all of the 

 processes by which it is treated. It is only by the possession of such 

 a complete knowledge of the entire history of a preparation that one 

 is able to judge with certainty of the comparative excellence of 

 methods, and thus to discard or improve those which are defective. 

 The teacher, as well as the investigator, should have this information 

 in an accessible form, so that not only he, but his students, can obtain 

 at any time all necessary information concerning the preparations 

 which serve him as illustrations and them as examples." 



525. Labeling ordinary microscopic preparations. The label 

 should possess at least the following information. 



The number of the preparation, its name and date and the thick- 

 ness of the sections and of the cover-glass. 



526. Cataloguing preparations. It is believed from personal 

 experience, and from the experience of others, that each preparation 

 (each slide or each series) should be accompanied by a catalogue con- 

 taining at least the information suggested in the following formula. 

 This formula is very flexible, so that the order may be changed, and 



