Repository: UIHistories Project: Mathematical Models Construction and Use of Mathematical Models (Fehr & Hildebrandt) [PAGE 16]

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IX,

Other

Models

There are-many other models which are valuable but laok of sT)aoo p e r m i t s n o e x p l a n a t i o n of them* 'Among such m o d e l s are m a p p r o j e c t i o n * s t o r e o g r a p h i c p r o j e c t i o n , the sextanty (Plate V , n o , 7 ) * sun dial*. (Plato V , n o , 1 ) , s t e r e o g r a m s * (Plato I I I * n o r 1 0 ) * l i n k a g e s * (Plate I I , n o , 2 ) * m a g i c cubes> d u p l i c a t i o n of the c u b e * and i n s c r c b c d r e g u l a r p o l y g o n s , A l s o m o d e l s for the non••Euclidian g e o m e t r y p a r a l l e l p o s t u l a t e , the t o s c r a c t and fourth dimensional geometry* projective geometry* spherical trigo n o m e t r y ^ and astronomy*, T h e f i e l d is r i c h and f r u i t f u l and every teacher of M a t h e m a t i c s can find n u c h aid in i t . This p a m p h l e t serves m e r e l y as a guide a n d an i n t r o d u c t i o n to w h a t should p r o v e to b e a m o r e f a s c i n a t i n g m e t h o d o f m a t h e m a t i c a l i n s t r u c t i o n , Xi Suggestions on Materials 1*. In making stiff paper models use index card and not cardboard* Index card comes in largo sheets of v a r i o u s c o l o r s * is l i g h t * s t r o n g , f l e x i b l e and -easy to handle*. L i b r a r y paste or other quick d r y i n g p a s t e should b e u s e d * All edges should be cut b y a sharp k n i f e or razor b l a d e * s l i d i n g along a straight edge* Do n o t u s e a s c i s s o r s • 2* In using celluloid for plane surfaces, use the heaviest sheeted m a t e r i a l * For curved surfaces u s e the light r o l l e d c e l luloid* The b e s t sealing m a t e r i a l is D u p o n t f s glue# Celluloid m o d e l s are c l e a r * t r a n s p a r e n t , and l a s t i n g b u t m u s t b e h a n d l e d w i t h care*. 3^ Ordinary plate glass is the best kind for glass models* M e a s u r e m e n t s should b e taken in advance and all g l a s s parts cut to size b y a glazier*. Glass c e m e n t or f u r n i t u r e glue is the b e s t s e a l i n g substance•. W h i l e such m o d e l s are h e a v y * easily b r o k e n , clumsy to h a n d l e , they m a k e e x c e l l e n t s t a t i o n a r y m o d e l s b e c a u s e of their transparency-. 4 , W o o d and m e t a l are the e a s i e s t m a t e r i a l s to h a n d l e and c an b e turned on a lath0-. M o d e l s m a d e f r o m t h e m are p e r m a n e n t and good for d e m o n s t r a t i o n purpos