[ 44 3 



marble, may be included here, though they 

 never form continued ftrata, being found only 

 in loofe independent maffes, as the marmoroidse, 

 containing fhells^ corals, and other extraneous 

 bodies, aftroites or ftar ftones, lea {tars, entro- 

 chus, belemnites, cornu ammonis, or fnake 

 jtone, &c. the remains of animals, which are 

 confequently of a calcareous nature (d). 

 c. Spars are calcareous bodies, found in mines, 

 attendant on ores, &c. whan pure, of a glafiy 

 appearance, and often cryftallifed into polygo- 

 nal figures, as common fpar, refracting fpar, 

 cryftallized fpar, ftalactites, ificle or dropftone. 



C. Gypsum or oyps ; a calcareous fubftance, 

 faturated with the vitriolic acid, and hence 

 does not efFervefce with acids ; falls into a white 

 powder when heated, and concretes again with 

 water into a mafs, which foon hardens, called 

 plafter or ftucco, as pi after- flone, alabafter, 

 fibrous pi after- ftone or fibrous talc, gypfeous 

 powder, felenites, &c. 



D. Talcs do not ftrike fire with fteel, nor efFer- 

 vefce with acids ; infoluble in water, and very 

 refractory in the fire per fe 9 but fufible with 

 borax. 



b. Micas, glimmers or daze, have a fcaly tex- 

 ture, the plates moftly running horizontally 

 parallel, eafily feparable, of various colors, as 



{d) The author does not attempt to give a complete 

 fyftem of foflils, but to comprize in as fhort and as fimple 

 a view as poffible the principal heads they comprehend, and 

 he conceives thefe bodies may not improperly Hand as above, 

 without introducing feparate divifions of petrifactions and 

 incruftations, the ftony fubftances fufpended by the water 

 being depofited upon mofles, roots, and branches of plants 

 forming the latter, 



green, 



