ed, In a curfory manner, by muriatic acid, but did not obtain any precipitate when water 

 was added to the filtrated folution. 



Upon mentioning this circumilancc, and expreffing a defire to examine this fubftaBoe 

 with more accuracy, Sir Jofeph Banks, with his ufual readinefs to promote every fcientific 

 enquiry, not only permitted me to take fpecimens from different parts of the box which 

 contained the earth already mentioned, but (that every doubt might be obviated) gave me 

 about 300 grains which remained of the identical fubftance examined by Mr. Wedgwood. 



Upon thefe the following experiments were made j and, to diftinguifli them, I (hali call 

 the firft, No. I,and that examined by Mr. Wedgwood, No. 2. 



SECT. 11. 



^na/yjis of the Sydnciz, No. i. 



THE Sydneia, No. r, is in mafles and lumps, of a pale greyifh white, intermixed with a 

 few particles of white mica, and alfo occafionally with fome which are of a dark grey, re- 

 fembling graphite or plumbago. 



It eafily crumbles between the fingers, to a powder nearly impalpable, which'has rather 

 an un£tuous feel. 



Small fragments of vegetable matter are alfo commonly found intermixed with it ; and 

 the general afpe£t is that of an earthy fubftance which has been depofited by water. 



Experiment i. — 400 grains were put into a glafs matrafs, and one quart of diftilied water 

 being added, the whole was boiled to one-fourth. 



The liquor was then filtrated, and a portion being examined by the re-agcnts commonly 

 ufed, afforded no trace of matter in folution. The remainder was then evaporated, with- 

 out leaving any rcfiduum. 



Experiment 2. About 2co grains of the earth, rubbed to a fine powder, were put into a 

 glafs retort, into which I poured three ounces of concentrated pure muriatic acid. The 

 retort was placed in fand, and the acid was diftilied, till the matter in the retort remained 

 dry. Two ounces of muriatic acid were again poured on it, and diftilied as before, till 

 only one fourth remained. The whole was then put into a matrafs, which was placed in 

 an inclined pofition, fo that, when the earth had fubfided, the liquor might be decanted 

 without difturbing the fediment. 



"When it had remained thus for 12 hours, the acid was carefully poured into a glafs 

 veffel : but, as I obferved that it was not fo perfedlly tranfparcnt as before it had been thus 

 employed, I fuffered it to remain 24 hours, but did not perceive any fediment. Half of 

 this liquor was diluted with about twelve parts of diftilied water, and, after a few hour^a, 

 a very fmall quantity of a white earth fubfided. 



in his Handbuch itt Naturgefchichte, p. 567, 568. mentions that he had examined a portion of this earthy 

 fubftance, by means of muriatic acid after the manner of Wedgwood, and obtained a flight precipitate ;— that 

 M- Klaproth had alfo examined it, whofe refults he likewife gives (for which fee the page of our Journal laft 

 mentioned) ; — and that the identity of the fubjefts examined by Wedgwood and Klaproth had been muqh 

 ijueftioned by ipe. The author tlien proceeds to relate the hillory ^nd particulars of his own analyfis, of 

 which the wordt of the text are ao.exaft copy. N. 



Vol. II.— May 1798. L ThJ» 



