1818.] Sir Terbern Bagman. 331 



appearance of this treatise, the method of analysing waters may 

 be considered as unknown. Several attempts, indeed, had been 

 made with more or less success ; but no general formula appli- 

 cable to waters in general had been thought of. Considerable 

 improvements have been recently made on the method of analyz- 

 ing mineral waters. This, indeed, was the natural consequence 

 of our more accurate knowledge of the exact composition of the 

 different salts which exist in mineral waters, and of the simplest 

 methods of detecting them and estimating their quantity. 

 Kirwan published a treatise on the same subject about the 

 beginning of the present century. But his methods are rather 

 too complicated for actual practice, and they seem scarcely 

 compatible with much precision. Dr. Murray's formula, published 

 in the eighth volume of the Transactions of the Royal Society 

 of Edinburgh, is, as far as it goes, the best and easiest method 

 of analyzing mineral waters. It seems unnecessary in the 

 present state of our knowledge to enter into any particulars 

 respecting Bergman's paper. For the same reason we may omit 

 his papers on the Waters of Upsala, on the Acidulous Spring in 

 the Parish of Denmark, on Sea Water, on the Artificial Pre- 

 paration of Cold Medicated Waters, and on the Artificial 

 Preparation of Hot Medical Waters. These papers were of 

 much utility at the time of their publication ; but at present the 

 science has made such progress, that they have lost a great deal 

 of their interest. 



4. On the Acid of Sugar. — This paper was originally written 

 as an inaugural dissertation, which was defended in 1776 by 

 J. A. Arvidson. Hence, doubtless, the reason why nothing was 

 said about the discovery of oxalic acid, and why it was generally 

 supposed at first by the chemical world that Bergman himself 

 was the discoverer of that acid. It is now known that the acid 

 in question was discovered by Scheele, who merely communi- 

 cated the process to Bergman. In this paper Bergman describes 

 the method of preparing oxalic acid, the properties by which it 

 is characterized, and the salts which it forms with 22 bases, all 

 that were known to exist at the period when this dissertation 

 appeared. 



o. On the Preparation of Alum, — This dissertation, which 

 has been mentioned repeatedly in the preceding biographical 

 account, contains a history of alum, a chemical examination of 

 its composition, a description of its ores, a minute description 

 of the processes followed by manufacturers, and a set of experi- 

 ni' nts undertaken with a view to improve these processes. Kven 

 at present this dissertation will be allowed to be excellent, and 

 alum makers would probably derive useful hints from a careful 

 perusal of it.. He was aware of the importance of potash and 

 ammonia, and owns that the facts would lead to the conclusion 

 that alum is a triple salt. But he rejects this supposition on 

 account of the fact that ammonia is equally efficacious in pro- 



