TO THE TEACHER. 



IT is not the fault of the teacher that the human body is very com- 

 plex in structure and that many of the functions are obscure. Never- 

 theless the teacher is responsible for making the subject as clear as is 

 possible. To do this it is absolutely essential to perform some experi- 

 ments and to show some of the internal organs of such an animal as 

 the rabbit, or materials obtained from the butcher. This involves 

 work, and sometimes work that is not altogether pleasant. But no 

 earnest teacher will shrink from work simply because it is not agreeable. 

 In the author's " Physiology, 'Experimental and Descriptive" (D. C. 

 Heath & Co.) are given in detail directions for many experiments and 

 dissections, some of which can be profitably used in classes in the 

 grammar grades. Each teacher should be provided with that book, 

 for in it are given lists of books helpful to the teacher, as well as of 

 books suitable for pupils to read in addition to their regular lessons. 



Every school should have a microscope, by means of which to show 

 the corpuscles of the blood, cells from various tissues, the circulation 

 of blood, in a frog's web, or in the gills of a tadpole. A good micro- 

 scope can be bought for from twenty to thirty dollars, and Clark's 

 "Practical Methods in Microscopy" (D. C. Heath & Co., $1.60) will 

 enable a beginner to make fair use of it. From various dealers in 

 school supplies there can be purchased mounted slides illustrating most 

 o'f the kinds of cells and tissues of the body. These can be success- 

 fully used by teachers who have not had the advantages of a thorough 

 training in histology. 



When studying the bones the teacher can usually borrow some 

 human bones from the nearest physician. Also get a femur of a horse 

 or cow and saw it in two lengthwise. It will show the structure as 

 well as a human femur. It is easy to test the composition of bone by 

 burning and by acid. Corned beef shows well the structure of muscle. 

 A sheep shank from the butcher may be used to show the joints, 

 synovia, cartilage, ligaments, etc. By following the directions in the 

 author's "Experimental Physiology" the brain and spinal cord of a 

 rabbit can be shown. Most pupils will be ready to help dissect a heart 

 and will be delighted to see the action of the valves. 



By means of a common bulb syringe and a little glass and rubber 

 tubing the action of the arteries and the nature of the pulse and capil- 



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