146 Scientific Notices — Chemistry. [Aug. 



3d. An Account of an Occultation of the Georgium Sidns by 

 the Moon, which will take place on the 6th of August next; by 

 Francis Baily, Esq. FRS. and V. Pres. Ast. Soc. — Mr. Baily 

 begged to call the attention of the Society to this interesting 

 phsenomenon which has never yet been seen, as no occultation 

 has occurred since the discovery of the planet. The occultation 

 will occur within a very few minutes after the moon has passed 

 the meridian ; insomuch that those persons possessing a transit 

 instrument will see the planet in the field of view when the 

 moon's centre is on the meridian. This notice was accompanied 

 by a diagram, showing that the planet would enter the western or 

 dark limb of the moon at about half way between the moon's 

 outer and the upper or northern part of her disk. There will be 

 sufficient time to observe the occultation of the planet after the 

 transit of the moon. This interesting phsenomenon will no 

 doubt attract the notice of every practical astronomer. 



This being the last meeting of the Society's present session, 

 an adjournment took place until the 12th of November next. 



Article XVIII. 

 SCIENTIFIC NOTICES. 



Chemistry. 



1. Cystic Oxide. Communicated in a Letter from Dr. Noeh- 



den to Mr. Children. 



MY DEAR SIR, 

 In a letter which I lately received from my friend, Prof. Stro- 

 meyer, he communicates some chemical information, which 

 may, perhaps, interest you, and which, therefore, I take a plea- 

 sure in imparting. " He had, some time ago," he says, " the 

 great satisfaction of discovering in gravel from the human body 

 Dr. Wollaston's cystic oxide : and afterwards in the urine of the 

 same patient, who is afflicted with the stone, the same substance 

 in considerable quantity. In this urine, the uric acid was 

 almost totally wanting, nor was the urea found in it in natural 

 quantity. As the cystic oxide has hitherto not been found in any 

 human concretions any where but in England, and has as yet 

 been nowhere observed in the urine itself, I wish you," he says, 

 " if you should see Dr. Wollaston, to mention this to him, at 

 the same time respectfully remembering me to him. I have no 

 doubt this intelligence will interest him. I mean shortly to pub- 

 lish a brief notice upon the subject, Last year, M. Lassaigne, 

 of Paris, also found cystic oxide in a stone from the bladder of a 



dog." 



If you wish to make any use of this information, you are 

 welcome to do so. 



I am, my dear Sir, yours sincerely, G. H. Noehden. 



