GLOSSARY AND INDEX OF TERMS. 



XI 



Opaque, p. 58. I 



Ore, 202. Also, by miners, a dis- 

 seminated ore and the including 

 stone together ; the term met- 

 al is often used for the pure ore. 



Oxyd, 73. 



Oxydizable. Capable of combining 

 with oxygen. 



Oxydating flame, 68. 



Pearly 55. 



Percolate. To pass gradually 

 through pores. 



Phosphorescence, 61. 



Pisolitic, [Lat. pisum, a pea,] com- 

 posed of large round grains or 

 kernels, of the size of peas. 



Pistachio-green. Green with yel- 

 low, and some brown. 



Plastic. Adhesive, and capable of 

 being moulded in the hands. 



Plumose. Having the shape of a 

 plume, or feather. 



Polarisation, 60. 



Polarity, 62. 



Polychroism, 57. 



Play of colors, 57. 



Plutonic rocks. Granite and allied 

 crystalline rocks. 



Polyhedral. [Gr. polus, many, and 

 hedrafzce.) Having many sides. 



Polymorphism, 44. 



Porous. Having minute vacuities, 

 visible or invisible to the naked 

 eye ; a loose texture, allowing 

 water to filtrate through. 



Porphyritic. Like porphyry, 340. 



Prisms, 23. 



Pseudomorphous, 54. 



Puddling Furnace. A reverbera- 

 tory furnace, U3ed in converting 

 cast into bar iron, after the finery 

 furnace. 



Pulverize. [Lat. pulvis, dust,] to 

 reduce to powder. 



Pulverulent. Like a fine powder 

 slightly compacted. 



Pyritous. Having the nature of 

 pyrites, 212. 



Pyro-electric, 62. 



Quartation, 318. 



Quartzose. Containing quartz as 

 a principal ingredient. 



Radiated, 53. 



Rake-vein. A perpendicular min- 

 eral fissure. 



Rectangle, 24. 



Reduction of ores, 204. 



Reduction flame, 68. 



Refraction, 58. 



Refractory. Resisting the actio 

 of heat ; infusible. 



Refrigerate. To cool. 



Regulus. The pure state of 

 metal, as regulus of antimony. 



Reniform. [Lat. ren, kidney,] 53. 



Replacement, 35. Resinous, 55. 



Resplendent. Having a brilliant 

 luster. 



Reticulated. [Lat. rete, a net,] 

 52, 54. 



Reverberatory furnace, 327. 



Rhombohedron, 27. 



Riddling or sifting of ores. Put- 

 ting the broken or pulverized ore 

 in a seive, and plunging the seive 

 into water, by which, the whole 

 powdered material is raised by 

 the water and the metallic part 

 sinking first, may be separated 

 to a great extent from the rest. 



Roasting. Exposing to heat in 

 piles, or in a furnace, and thus 

 driving off any volatile ingredient. 



Saccharoid. [Gr. sakchar, sugar.] 

 Having a texture like loaf sugar. 



Saline, (Lat. sal, salt.) Salt like ; 

 containing common salt. 



Salt. In chemistry, any combina- 

 tion of an acid with a base, 74. 



Scale of hardness, 64. 



Schlich. The finely pulverized ore 

 and gangue. 



Schistose. Having a slaty structure. 



Scopiform, (Lat. scopa, a broom.) 

 Like a broom in form. 



Scoria, (L. scoria, dross,) 205, 341 



Secondary forms, 34. Sectile, 65 



Semitransparent, 58. 



Shaft. A vertical or much in 

 clined pit, cylindrical in form. 



