MODE IX. GYPSUJVf. 483 



The distinction between gypsum and alabas- 

 ter may be regarded as more wide than that be- 

 tween limestone and marble, though chemical 

 writers arrange alabaster as merely a compact 

 gypsum ; but the artist, and the antiquary, and 

 even the common observer, consider alabaster as 

 a distinct substance. 



As limestone may be called a coarse marble, 

 and when calcined forms lime, so gypsum may 

 be regarded as a coarse alabaster, which when 

 calcined forms what is called plaster of Paris, 

 because the best is made of the gypsum of 

 Montmartre, in the neighbourhood of that city; 

 and the alabaster of the moderns, or compact 

 sulphate of lime, has, like marble, been em- 

 ployed by the sculptor and the architect, being 

 of a fine grain, and of a whiteness which has 

 become proverbial. The tombs of the middle 

 ages are sometimes of alabaster, yet more gene- 

 rally, it is believed, of alabastrite; but this has 

 seldom been examined; for while every parish 

 has its antiquaries, we have few mineralogists. 



Some kinds of gypsum and alabaster, as the 

 earthy and fibrous, with the crystallised, called 

 selenite or moon-stone, as it somewhat resembles 

 the gleam of the moon in water, are founcf in 

 veins and nodules, and belong to lithology. In 

 literary composition, as in painting, the eye 



