INDEX. 275 
Pottery, how made, 73 
Powder blue, of what made, and use of, 222 
Prince's metal, what it is, and for what used, 187 
Printer's types, of what made, 205, 218 
Pumice, description and use of, 67 
Pyrites, description, properties, and uses of, 198, 199 
Q. 
Quartz, description, properties, and uses of, 44 
, rock, 231 
Queen's ware pottery, of what made, 73 
Quick lime, how made, 98 
Quicksilver. See Mercury. 
R. 
Red chalk and Reddle, description and uses of, 199 
Realgar, description and uses of, 214 
Rocks, systematic arrangement of, 7, 224 
, primitive, description of, 224 
, secondary, 231 
, transition, 232 
, floetz or flat, 233 
, volcanic, 235 
Rock oil. See Naphtha. 
Roe stone. See Ketton stone. 
Roofing slate, description of, 76 
, how to choose, 77 
-, Welsh and Westmoreland, 78 
, French, 76 
-, various uses of, 77 80 
Rolling stones, of what made, 234 
Rotten stone, description and use of, 76 
Rouge, of what made, 84, 91 
Rubellite, valuable specimen of, 41 
Ruby, Oriental, description of, 31 
-, whence imported, value, properties, and uses of, 31, 32 
-, spinel, description, value, and uses of, 32 
, Balais, 32 
, false, 49 
Ruin marble. See Florence marble. 
S. 
Sal ammoniac, description of, how made, and uses of, 138, 139 
Salt, common, description and uses of, 129 
mines in Poland, description of, 129 
mines in Chester, 130 
, mountains of, in Spain, 130 
springs, 131 
