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Of the fix families of this fpecies I fhall defcribe only one, 

 namely that which has been moft advantageoufly employed as a 

 manure. Defcriptions of the other five fhould be found in 

 treatifes of mineralogy. It is called Jibrous gyp/urn. 



Its colours are grey, yellowifh or reddifh, or filvery white, 

 or light red, or brownifh yellow, or ftripcd with one ot more 

 of thefe dark colours. It is compofed of fibres or flrias cither 

 ftraight or curved, parallel or converging to a common centre, 

 fometimes thick, fometimes fine and fubtile, adhering to each 

 other and very brittle — its hardnefs fuch as to admit being 

 fcraped with the nail — commonly femitranfparent, in fome often 

 in a high degree. 



Ashes. Sifted coal afhes, thofe of peat, and white turf afhes, 

 have been found ufeful. Red turf afhes ufelefs and generally 

 hurtful. Wood-afhes have alfo been employed advantageoufly 

 in many cafes ; they contain either the four primitive earths, 

 as Mr. Bergman aflerts, or calcareous earth chiefly, according 

 to Achard, or calcareous and magnefia, according to D'Arcet. 

 They alfo contain fomc proportion of phofphorated felenite, 

 I. e, calcareous earth united to the phofphoric acid. Almoft all 

 contain alfo a fmall and variable proportion of common fait, 

 and Glauber's fait, and terrene falts, which, when in a fmall dofe, 

 all accelerate putrefadion ; alfo fmall bits of charcoal. 



CHARCOAL is a fubftance well known ; it has frequently and 

 fuccefsfully been ufed as a manure, ifl; Young's Annals, 152, && 



Soap 



