3 02 



POPULAR SCIENCE MONTHLY. 



Thousands upon thousands of persons handle our silver dollar, 

 but few happen to observe the lion's head which lies concealed in the 

 representation of the familiar head of Liberty; frequently even a care- 

 ful examination fails to detect this hidden emblem of British rule; 

 but, as before, when once found, it is quite obvious (Fig. 2). For simi- 

 lar reasons it is a great aid in looking for an object to know what to 

 look for; to be readily found, the object, though lost to sight, should 

 be to memory clear. Searching is a mental process similar to the 

 matching of a piece of fabric in texture or color, when one has for- 

 gotten the sample and must rely upon the remembrance of its appear- 

 ance. If the recollection is clear and distinct, recognition takes place 

 when the judgment decides that what the physical eye sees corresponds 

 to the image in the mind's eye; with an indistinct mental image the 



Fig. 2. — In order to see the lion's head, hold the dollar exactly inverted and the head will be 

 discovered lacing the left, as above outlined. It is clearer on the dollar itself than in this 

 reproduction. 



recognition becomes doubtful or faulty. The novice in the use of the 

 microscope experiences considerable difficulty in observing the ap- 

 pearance which his instructor sees and describes, and this because his 

 conception of the object to be seen is lacking in precision. Hence 

 his training in the use of the microscope is distinctly aided by con- 

 sulting the illustrations in the text-book, for thev enable his mental 

 eye to realize the pictures which it should entertain. He may be 

 altogether too much influenced by the pictures thus suggested to his 

 mental vision, and draw what is really not under his microscope at 

 all; much as the young arithmetician will manage to obtain the 

 answer which the book requires even at the cost of a resort to very 

 unmathematical processes. For training in correct and accurate 

 vision it is necessary to acquire an alert mental eye that observes all 

 that is objectively visible, but does not permit the subjective to add 

 to or modify what is really present. 



