1 82 Scientific Intelligence. 



3. Dispute concerning the Glass of the Great Dorpat Telescope. — M. 

 Utzschneider has published a reclamation, denying that the glass of this 

 celebrated instrument was made by M. Guinand. The Editor of the Bi- 

 bliotheque Universelle, who is particularly charged with having made this 

 mistake, refers to this Juvrnal as its authority, viz. No. iv. of our Old 

 Series, p. 303, 1825 ; so that the force of M. Utzschneider's complaint is 

 directed against us. 



' j;We knew' well that M* Guinand werit to M. Utzschneider's establishment 

 at Benedictbaiern near Munich, to communicate his methods, and to put 

 them in practice. All this he did ; — and we know, moreover, that he did 

 possess the art of making very superior glass, as the report of the Astrono- 

 mical Society of London proves. 



With this information we stated, that, by means of glass made by M. 

 Guinand's method, M. Fraunhofer constructed achromatic telescopes far 

 superior to any hitherto made ; or, if it shall be thought a better interpre- 

 tation of our words, we have stated, that, by means of M. Guinand's glass, 

 M. Fraunhofer has constructed such telescopes, &c. 



Here there is no statement either direct or implied that the glass of the 

 Dorpat telescope was made either by M. Guinand or by his methods, and 

 we think that the Editor of the Bibliotheque Universelle has committed an 

 oversight in throwing the blame upon us. 



M. Utzschneider, we presume, will not deny our assertion, that M. Fraun- 

 hofer did construct superior achromatic telescopes by means of M. Gui- 

 nand's glass. 



The following are the passages referred to: '* The great discovery of a me- 

 thod of making flint glass in large pieces and perfectly pure, and free froni 

 striae, which was made by the late M. Guinand, and of which we have 

 ^iven a full account in this Number, may be considered as forming an era 

 in the history of the Achromatic Telescope. 



*' By means of this glass M. Fraunhofer has constructed achromatic 

 telescopes far superior to any that have been hitherto made." — Edin- 

 burgh Journal of Science, vol. ii. or No. 4, April 1825, p. 305. 

 " i ** Si dans ce meme article, il nous est arrive de citer parmi les produits 

 Tdti talent de Mr Guinand, I'objectif du Telescope de Dorpat, ce nest que 

 parce que cet olijectiflui a etc aitribue par plusieurs jour naux, en particu- 

 lier, par le Journal of Science of Edinburgh. (T. ii. p. 305, 1825.) 

 Bibl. Univers. vol. xlii. No. 1, September 1829, page 73. 



II. CHEMISTRY. 



4. Oxygen in Lithia.^^k Russian chemist in Moscow has lately found 

 in lithia upwards of 10 per cent, more oxygen than was given by the high- 

 est results of Vauquelin, Gmelin, or Arfwedson. By a repetition of his 

 iexperimcnts, Berzelius has obtained nearly 55 per cent, for the oxygen in 

 this earth. Berzelius supposes this high result to be owing to the great 

 purity of the lithia transmitted to him from Moscow. The experiments, 

 when published, will be of great interest. J. 



- '^hv thdine and Bromine in Salt Spi'ings and Mineral Waters in Eng- 



