Some Mechanical Aids in Nature-Study 



William Gould Vinal 



The Rhode Island Normal School 



That there should be artificial devices for teaching nature-study 

 ideas seems rather contradictory. The writer fully realizes that 

 mechanical aids are powerless to educate but believes them to be 

 convenient tools for the skilled workman. A large supply of 

 nature-study machinery, therefore is not to be confused with 

 progress. 



Originality is not claimed for the following schemes. Some are 

 inherited with various changes from past instructors while others 

 are the sum and epitome of several years of experience. Such well 

 known contrivances as the germination box with sloping glass 

 front to exhibit root characters are not included in this article. 

 Stories and anecdotes to illuminate certain points, as in the case of 

 the noted scientist who made the difference between the terms 

 specie and species clear by saying that specie is something with 

 which biologists have little to do, are left for a separate sketch. 



General Aids 



i. Aquaria. The salt water aquarium should be used to a 

 greater extent. Sea-salt may be purchased or obtained by 

 evaporation of sea water. Sea lettuce (Ulva) may be floated on 

 the surface by means of corks. Do not over-populate the jar. 



A metal plug with a pin-hole bore, placed in the opening of the 

 faucet, makes a fine stream which is excellent for a ration. 



2. Blackboard. Linoleum, framed and reenforced at the back, 

 makes an excellent blackboard. 



Wires stretched along the top of the blackboard and also five or 

 six inches above the ledge are very serviceable. The latter is 

 convenient for holding pictures on the sill. The pictures can be 

 placed there or removed very quickly without injury by patent 

 fasteners. 



Frames the size of the blackboard sections, covered with cloth, 

 can rest upon the sill and be attached at the top by means of screw 

 eyes. These are useful for pinning on clippings, announcements, 

 etc. They are also handy for exhibitions. Fall fruits look very 

 attractive when pinned upon them. 



(M) 



