34 ELEMENTARY ZOOLOGY. 



qualities you have written of the objects and determine by means 

 of what sense you discovered each? Are any of the observations 

 obtained by the combined work of two or more senses? What sense 

 do you use to determine that the pebble has weight? Just how do 

 you observe "roughness"? In what way do we get our idea of 

 the form of objects? How many elements are included under 



"form"? 



Just what do you observe? the object itself or the qualities and 

 properties of the object? 



Do people differ in their powers of observation chiefly because 

 of difference. in clearness of vision, sensitiveness of touch, and sharp- 

 ness of taste? What then? What is the difference in your individ- 

 ual mental attitude when you are observing carefully and accurately, 

 and when you are not? 



(Be sure that your observations are properly recorded; that your 

 notes really say what you want them to say and only that. Accurate 

 statement is almost as essential as accurate observation.) 



b. Comparison of the Qualities of an Object. Are certain of these 

 enumerated qualities more closely connected with each other? 

 Are color and translucency more nearly related than either is to 

 shape ? Compare all the statements you make of one class of objects, 

 and bring together under proper headings those that fall more natur- 

 ally together, as form, size, outline, etc.; structure, composition, 

 etc.; activities, powers, etc. ; and so on through the list. 



Just how does your mind work while comparing? What is the 

 value in being able to do this? 



c. Discrimination of Qualities. Are all the qualities which you 

 observe of an object equally important and fundamental to the 

 object? Is the ease or difficulty of observing a quality the thing 

 that determines whether it is important or not? How, then, can we 

 tell when a quality is an important one? 



One of the most important powers'for the pupil to acquire, either 

 for successful laboratory work or for life, is the power to distinguish 

 between essential things and incidental things; and yet the student 

 must be cautioned against being too sure thkt a quality is unessential. 

 Features of seemingly slight value often prove important. 



One of the greatest advantages of laboratory work in the biological 

 sciences is the cultivation of this power of discrimination. 



d. Comparison of Objects on the Basis of Their Important Char- 

 acteristics. What is the value of this? Can we compare objects 

 directly? How did you compare sand and pebbles? 



Comparison brings out two classes of relations: agreements and 

 disagreements. Both are important. 



