vi.] ON THE STUDY OF ZOOLOGY. 97 



mind of the student is brought into immediate contact with 

 facts upon the degree to which he learns the habit of appealing 

 directly to Nature, and of acquiring through his senses concrete 

 images of those properties of things, which are, and always will 

 be, but approximatively expressed in human language. Our 

 way of looking at Nature, and of speaking about her, varies from 

 year to year ; but a fact once seen, a relation of cause and 

 effect, once demonstratively apprehended, are possessions which 

 neither change nor pass away, but, on the contrary, form 

 fixed centres, about which other truths aggregate by natural 

 affinity. 



Therefore, the great business of the scientific teacher is, to 

 imprint the fundamental, irrefragable facts of his science, not 

 only by words upon the mind, but by sensible impressions upon 

 the eye, and ear, and touch of the student, in so complete a 

 manner, that every term used, or law enunciated, should after 

 wards call up vivid images of the particular structural, or other, 

 facts which furnished the demonstration of the law, or the 

 illustration of the term. 



Now this important operation can only be achieved by con 

 stant demonstration, which may take place to a certain imperfect 

 extent during a lecture, but which ought also to be carried on 

 independently, and which should be addressed to each individual 

 student, the teacher endeavouring, not so much to show a thing 

 to the learner, as to make him see it for himself. 



I am well aware that there are great practical difficulties in 

 the way of effectual zoological demonstrations. The dissection 

 of animals is not altogether pleasant, and requires much time ; 

 nor is it easy to secure an adequate supply of the needful speci 

 mens. The botanist has here a great advantage ; his specimens 

 are easily obtained, are clean and wholesome, and can be 

 dissected in a private house as well as anywhere else; and 

 hence, I believe, the fact, that botany is so much more readily 

 and better taught than its sister science. But, be it difficult 

 or be it easy, if zoological science is to be properly studied, 

 demonstration, and, consequently, dissection, must be had. 



H 



