NEW^ VARIETY OF CAUCONATE OF LIME. 359 



VI. 



Descripilon of a new Varkfij of Carbonate of Lime. Bj/ 

 R. J. IIauy*. 



JLN my Treatise on Mineralogy I described forty-seven de- 71 varieties of 



terminate varieties of form in carbonate of lime. About '■^'■l^"'iate of 



lime known. 

 two years after I pnblished in the Annals of the Museum 



of Natural History a memoir containing a description of 

 thirteen more varieties of the same substance, making to- 

 gether sixty; and since that time I have observed eleven, 

 equally marked with novelty, so that at present the number 

 of forms presented by this species amounts to-scventy one. 



This number is trilling to what theory demonstrates to be Above 8 mil- 

 possible, which exceeds eight millions, even supposing we '""^P^^pi le, 

 confine ourselves to the four simplest laws of decrement. 

 But I am far from considering the formula, that has led me 

 to this result, as exhibiting the sum of past and future dis.» 

 coveries; and we need not fear being perplexed at some fu- butcircum- 

 ture period by our abundance, if we consider, that among ^'f"^'^,'^^'^"'" 



r J . . o site to the pro- 



the circumstances capable of determining the production ofduction of all 

 this immense quantity of crystalline forms there are a great °' ^^'*^' 

 number, that do not exist in nature. The formula to which 

 I allude merely shows us how fertile the laws of the struc- 

 ture of crystals are in themselves ; and teaches us, that 

 Science has in her hands certain means of determining with 

 precision all the new forms, that may present themselves to 

 mineralogists in the course of their researches, however va- 

 ried they may be, and however little analogy they may bear 

 in appearance to those that arc already known. 



The very steps that Science takes in her progress, in pro- Only a small 



portion as she enriches herself by discovery, indicate, thatP^'^.p^ things 

 , - . f -, . . possible actu- 



what does exist is connned to very narrow limits compared ally exist. 



with what is capable of existing. The new varieties of car* 



bonate of lime, that have been found within these few 



years, are almost all of them but different combinations of 



laws already observed, and the greatest of these combina- 



iions does not include above six quantities. 



* Journal des Mines^ vol. XVIII^ p, 299. 



