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If possible, get the pupils (some of theui will have the interest and 

 patience to do so) to prepare for the use of the class, the skeleton of a 

 fish, salamander, frog, bird and mammal (rabbit, cat or dog). Even if 

 these skeletons are not mounted, but in separate pieces, they can be 

 made use of with great advantage. Let each skeleton be considered in 

 relation to the kind of motion that each animal has. 



The bones of a dog or cat are very much the same in every form as 

 those of the human skeleton, and have the same names. Have the pu- 

 pils see how the bones compare in the series, say the humerus, femur, 

 or phalanges in all. In each case see how it is adapted to the use of the 

 animal. 



A study of the lever in its different forms, the first, second and third 

 class, as they are known, may be made with a ruler. 



A convenient piece of apparatus for study of the different classes of 

 levers may be constructed as follows: A support for the lever consists of 

 a stand with a wooden base about i8 by 8 inches. Fromi the center 

 arises an upright piece 12 inches high, 1% by 2 inches. In the top of 

 this is a slit to receive a rod of w'ood which is to act as the different 

 forms of levers. The rod is a little more than two feet long. It works 

 on a nail as a pivot, which passes through the prongs of the slit and the 

 center of the rod, the one half balancing the other. It has 12 holes, one 

 inch apart, on each side of the center. Some wire hooks can be placed in 

 the holes and used to support weights . Now with these weights and by 

 pulling up on the hooks, all forms of the lever may be studied. A 

 spring balance may be used to pull up with. The diflFerent distances 

 necessary for weights to be supported by different powers, and in what 

 direction, may be seen. 



After studying levers, find application in different kinds of tools and 

 implements, the loss and gain of power, weight and velocity in each 

 case. Then question about each of the bones to ascertain the case with 

 each. 



The Pine Tree. 



Just at this time of the year the pine trees about the city may be ob- 

 served vrith interest. The growing branches, the main axis of each, the 

 terminal bud and the small side branches containing the young needle 

 leaves may be made objects of observation. The branches which be- 

 come flowers may be noted. The one kind furnishes an immense 

 amount of pollen, the other constitutes the young cones. In the one see 

 just how the pollen grain is borne; in the other, just where the ovules are 

 located, that is just at the base of the scales making up the cone. In 

 the older cones, find the seeds. These have developed from the fertil- 

 ized ovules. The ovules must receive the pollen grains before they can 

 develop into seeds. How does the pollen reach them? The settling of 

 this question will bring out the advantage in producing such immense 



