5 6 FußbilUy. Caix and Argill. Heat.j Of Binary Proportions. 75 calx 25 argill 66 calx 33 argill 150 *5° 66 argill 33 calx 75 argiil 25 caix 80 argill 20 ca!x 50 calx 50 argill } Calx and Silex. Co calx 50 lilej? 50 calcareousfpar 50 quartz 80 ßkx 20 calx 80 calx 90 lilex not nielted, except where in contatt with the crucible it formed a compaft porcelain brovvnilh red mafs. remained a powder. Henee the contrary refulta ob- tained hy Achard feem to proceed from the athion of the mixtüres on the fdex of the crucible. Mr. Bergman a'fo found calx and ar gill infufible in all proportions. 4 Berg. 3,3 7, and Macquer. Mcm. Paris, '758, 336 in Svo. fmelt by pure air. Ehrm. § 208. -< infulible, per Achard, Mem. {_Bcrl. 1780. 65. | melt by pure air, ibid; infu- 1 üble per Achard, ibid. Jmelt by pure air, ibtd; infu- [ fible, Athara, ibid. f infufible, Achard, loc. cit. and •C formed only a loole povvder in ^tfiis as in the former Cafes. ;5o .56 1 ;6 melted itito a mafs bctwcen porcelam and an eramcl; white, glazed on the furface, femi- tranfparent at the edges, and gavc fire with fieel, though feebly. Yet Mr. Achard for.r.d them infufible in every propor- tion, perhaps becaufe his caix was mild. melted by pure air, Lavoifier; 1 but by contmued heat became (_lefs fufible. notmeited. formed a brittle mafs. | formed a yellowilh white loofe { povvder. Baryte»