140 



> OBJECT-HOLDER 



B 



D 



INCISION No I. 



PLASTIC UNIT 



/NC. No. 2. 



/NC. 

 No. 5. W- 



D, 



Fig. 260. Moulding of the pyramid. (N.B. Plastic unit 4:1, object-holder 

 about 2:1.) — A. Incision No. 1. — B. The object-holder is turned 180° 

 and incisions Nos. 2 and 3 are made. A part of the apex of the plastic unit 

 will fall away with incision No. 3, after which the object-holder is turned 

 again 180°. — C. Incision No. 4 cuts off the other part of the apex of the 

 plastic unit. Two sides of the pyramid are now ready. The object-holder is 

 then turned 90°. — D. Incision No. 5. Dj shows the object-holder with 

 the plastic unit in top perspective after incision No. 5. — E. The object- 



