CHAPTER IX. 



THE DELINEATION OF OBJECTS MICROSCOPIC 

 MEASUREMENTS. 



WE have now to dilate upon the importance of sketching 

 everything of interest the observer may see under the 

 microscope. 



Dr. Beale says: "The student cannot too soon try 

 to delineate what he demonstrates. He will teach himself 

 to observe the more accurately and the more quickly if he 

 record the results of his work in pencil sketches. A truthful 

 drawing of what a man has recently seen may be compared 

 with drawings made 100 years hence ; and although the 

 means of observation will be more perfect than they are at 

 present, such comparisons may be useful in many ways, 

 and especially in preventing erroneous conclusions from 

 becoming popular." 



It cannot be too strongly impressed upon the reader, of 

 the advisability of frequent practice with the various 

 means devised for this purpose. Microscopical contribu- 

 tions to our scientific papers, communications to societies, 

 and even the results of our every-day observations, all 

 become more interesting if illustrated in some way or 

 other. 



There are many methods by which microscopical objects 

 may be delineated. They may be roughly drawn by means 

 of pencil and paper, guided by the eye alone or assisted 

 with the use of a circle of glass ruled into squares, made to 

 rest upon the diaphragm of the eye-piece ; the paper, in 



