37G PLINY'S KATUUAL HISTOUT. [Book 



CHAP. 59. GYPSUM. 



Gypsum* 5 has a close affinity with limestone, and llicrc arc 

 numerous varieties of it. One kind is prepared from u cal- 

 cined 57 stone, as in Syria, and at Thurii, for example. In 

 Cyprus and at Perrluubia,* gypsum is dug out of the earth, 

 and at Tymphcea w it is found just beluw the level of- the soil. 

 The stone that is calcined for this purpose, ought to be very 

 similar to alabastrites, GO or else of a grain like that of marble. 

 In Syria, they select the hardest stones for the purpose, and 

 calcine them with cow-dung, to accelerate the process. Ex- 

 perience has proved, however, that the best plaster of till is 

 that prepared from specular-stone,* 1 or any other stone that is 

 similarly laminated. Gypsum, when moistened, must be used 

 immediately, as it hardens with the greatest rapidity ; it 

 admits, however, of being triturated over again, and HO reduced 

 to powder. It is very useful for pargetting, arid has a 

 pleasing effect when used for ornamental figures and wreaths 

 in buildings. 



There is one remarkable fact connected with this substance ; 

 Caius Proculeius, 62 an intimate friend of the Emperor Augustus, 

 Buffering from violent pains in the stomach, swallowed gyp- 

 sum, and so put an end to his existence. 63 



CHAP. GO. (25.) PAVEMENTS. T1IE ASAROTOS CECOS. 



Pavements are an invention of the Greeks, who also prac- 

 tised the art of painting them, till they were superseded by 

 mosaics. 6 * In this last branch of art, thr highest excellence 

 has been attained by Sosus,* 5 who laij, at Pergamus, the 

 mosaic pavement known as the " Asarotos cccos;" 06 from the 

 fact that he there represented, in small squares of different 

 colours, the remnants of a banquet lying upon the pavement, 

 and other things which are usually swept away with the broom, 



56 The name now given to Sulplmtu of lime, including the varieties of 

 Alabaster and Selenite. Plaster of Paris is prepared from it. 



67 The method of preparing plaster of Paris. M Sec B. iv. c. 3. 



See B. iv. c. 3. 



60 The same thing-, strictly speaking. See Chapter 12 of this Book. 

 1 See Chanter 45 of this 'Book. 2 See B. vii. c. 40. 



Dioscorides says, B. v. c. 134, that, taken internally, it produces suffo- 

 cation. " Lithostruta." 



* His age and country arc unknown. 



66 "The Louse that has no sweeping." 



