376 Flint's natural history. [Book XXSVI* 



CHAP. 59. GYPSUM. 



Gypsum^^ has a close affinity with limestone, and there are 

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

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

 Cyprus and at Perrhasbia,^^ gypsum is dug out of the earth, 

 and at Tymphsea^^ it is found just below the level of the soil. 

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

 similar to alabastrites,^" 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 all is 

 that prepared from specular- stone," 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 so reduced 

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

 pleasing effect when used for ornamental figures and wreaths 

 in buildings. 



There is one remarkable fact connected with this substance ; 

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

 suffering from violent pains in the stomach, swallowed gyp- 

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



CHAP. 60. (25.) — PAVEMENTS. THE ASAEOTOS (EGOS. 



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

 tised the art of painting them, till they were superseded by 

 mosaics."^ In this last branch of art, the highest excellence 

 has been attained by Sosus,*^ who laid, at Pergamus, the 

 mosaic pavement known as the " Asarotos oecos;"^ 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, 



5^ The name now given to Sulphate of lime, including the varieties of 

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



" The method of preparing plaster of Paris. ^^ See B. iv. c. 3. 



59 See B. iv. c. 3. 



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



<5i See Chapter 45 of this Book. ^2 gee B. vii. c. 46. 



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

 cation. 64 u Lithostrota." 



*^' His age and country are unknown. 



^^ "The house that has no sweeping." 



