292 PHILOSOPHICAL TRANSACTIONS. [ANNO J 798. 



glimmer or micaceous iron ore. The other contained much less of these black or 

 dark grey particles, and, as he considered it to be more pure than the former he 

 subjected it to the following experiments. 1. It was digested at 3 different times 

 with concentrated muriatic acid, in a boiling heat, and the acid was afterwards fil- 

 trated through paper. The solution was then mixed by degrees with pure water, 

 which did not however produce any precipitate, even when warmed. Carbonate of 

 pot-ash caused some flocculi to fall, which, edulcorated and dried, weighed 3.25 grs. 

 This precipitate was dissolved in diluted sulphuric acid, and left a small portion of 

 siliceous earth; after which the solution, by evaporation, afforded crystals of alum. 



2. The residuum of the muriatic solution was mixed with 3 times the weight of 

 pot-ash, and exposed to a red heat. Muriatic acid was then poured on the mass, 

 and the insoluble gelatinous residuum was edulcorated on a filter; and, after a red 

 heat, weighed 19.50 grs., which proved to be siliceous earth. 3. The muriatic so- 

 lution, with prussiate of pot-ash, afforded a blue precipitate; the ferruginous part 

 of which was about 4- gr. 4. The solution was then saturated with carbonate of 

 pot-ash, and some alumine was precipitated; which, after a red heat, weighed 

 8.50 grs., and with sulphuric acid formed alum. Siliceous earth, alumina, and 

 iron, appeared therefore to be the only ingredients of this substance; but, as Mr. 

 Klaproth had no more than 30 grs. to examine, he could not extend his experi- 

 ments. 



From those above related, he is of opinion that the existence of this primitive 

 earth may be much doubted, and that this doubt can only be removed in the course 

 of time, by other analyses. Mr. Klaproth concludes his memoir by saying, that 

 the substance examined by him was undoubtedly the genuine austral sand, as Mr. 

 Haidinger had received it from Sir Jos. Banks, when he was in London. 



Mr. Nicholson however, in the 9th N° of his Journal of Nat. Philos. &c. p. 410, 

 published on the 1st of Dec. 1797> questions much, whether the substance exa- 

 mined by Mr. Klaproth was the same as that examined by Mr. Wedgwood; and, 

 after having contrasted their experiments, says, " hence it seems fair to conclude 

 that the 2 minerals were not the same, however this may have happened; and that 

 the existence of the new fusible earth of Wedgwood stands on the same evidence 

 as before, namely, his experiments, which have not yet been repeated, that I know 

 of." Some of Mr. Nicholson's objections to the experiments of Mr. Klaproth, 

 being founded principally on some difference in the external characters of the sub- 

 stance examined by him, and the one examined by Mr. Wedgwood, are such as 

 very naturally occur; but the following pages will I believe prove, that Mr. Klap- 

 roth's experiments were made on that which might be justly regarded as the Sydneia 

 or austral sand. 



In 1796, Sir Jos. Banks, p. b. s. favoured me with a specimen of the Sydneia, 

 which has been lately brought to England; a portion of this I soon after examined, 

 in a cursory manner, by muriatic acid, but did not obtain any precipitate when 

 water was added to the nitrated solution. On mentioning this circumstance, and 



