Page:The New International Encyclopædia 1st ed. v. 13.djvu/597

* MINERALOGY 1. Normal crystal form developed equally in all dlrec- 4. Network of molecules formed on the lines of 2. Same crystal form as 1, distorted. 5. Further development of network shown In 4 to 3. Crystal molecule showing an arrangement of at- explain cleavage. tractive and repellent forces. 6. Twin crystal formed by two interpenetrated cubes.
 * 'Ons. crystallizing forces shown in 3.