2 '-LABORATORY LESSONS IN GENERAL SCIENCE 



' 3. While. t'ic left wrist is held in a close grasp by the right 

 hand, observe any movements through the wrist as the 

 fingers of the left hand are moved 

 about. Explain what is seen and felt. 

 Take firm hold of the forearm just 

 below the elbow; move the fingers 

 freely, and explain any movements 

 noted in the arm. What purposes are 

 served by having these muscles so far 

 away from the parts moved by them ? 



4. By what other means than the 



Tendon. 



use or many muscles is variety in 



movements of the hand secured? 

 Count the bones (a) in each finger, 

 and in the thumb; (6) across the 

 Muscle, fS^SBIlH thick part of the hand. What pur- 

 poses are served (a) by binding to- 

 gether the bones forming the palm 

 of the hand ; (6) by having the thumb 

 so loosely connected? What advan- 

 tage results from having one less 

 bone in the thumb than in a finger? 



FIG. 1. Muscles and ten- 

 dons of the hand and T xn .Li- 

 forearm. 5. What name is given to the inner 



side of the thick part of the hand? 

 What, is the name given to the union of any two 

 bones? What special name is given the places where 

 the fingers are joined to the hand ? What kind of motion 

 only is possible in the joints of a finger? Wliat purpose 

 is served by these limitations in the freedom of finger 

 movements ? 



