BOOK XXXV. Lvn. i^^-lviii. 199 



from Sardinia, is only used for white fabrics, and is of 

 no use for cloths of various colours ; it is the cheap- 

 est of all the Cimolus kinds ; more valuable are 

 the Umbrian and the one called ' rock.' ° The 

 peculiarity of the latter is that it increases in size 

 when it is steeped in Hquid ; consequently it is sold 

 by weight, whereas Umbrian is sold by measure. 

 Umbrian earth is only employed for giving lustre to 

 cloths. It will not be out of place to touch on 

 this part of the subject also, as a Metilian law refer- 

 ring to fullers still stands. the law which Gaius 

 Flaminius and Lucius Aemilius as censors put forward 220 b.c. 

 to be carried in parliament : so careful about every- 

 thing were our ancestors. The process then is this : 

 the cloth is first washed with earth of Sardinia, and 

 then it is fumigated with sulphur, and afterwards 

 scoured with Cimolian earth provided that the 

 dye is fast ; if it is coloured with bad dye it is 

 detected and turns black and its colour is spread by 

 the action of the sulphur; whereas genuine and 

 valuable colours are softened and brightened up 

 with a sort of brilliancc by Cimolian earth when 

 they have been made sombre by the sulphur, The 

 ' rock ' kind is more serviceable for white garments, 

 after the application of sulphur, but it is very detri- 

 mental to colour. In Greece they use Tymphaea 

 gypsum instead of Cimolian earth. 



LVIII. There is another cretaceous earth ^ called sihersmiths' 

 silversmiths' powder as used for polishing silver ; ^"'"'^' 

 but the most inferior kind is the one which our 

 ancestors made it the practice to use for tracing 

 the hne indicating victory in circus-races and for 

 marking the feet of slaves on sale that had been 

 imported from over-seas ; instances of these being 



407 



