i§^@-3 SeientiJicNqticei'--Miscellan€ous. 395 



2. Analysis of Lamp-blach • 



The same chemist has analysed lamp-black, which gave him, 



Carbon o\ 



Water 8-0 



"Resin, similar to that found in a fossil state near London,* 



and examined by Thomson p"3 



Sulphate of ammonia 3'3 



Asphaltum, or bitumen of Judsia 1' ' 



Sulphate of hme O'^ 



Quartzose sand O'O 



Ulniin, about ^'^ 



Sulphate of potash 0*4 



Phosphate of lime, very ferruginous 0-3 



phloride of potassium Trace 



100-00 



M. Braconnot concludes from these analyses, " that all soots 

 contain essentially several sulphates. The presence of a notable 

 quantity of sulphate of ammonia in lamp-black, renders that 

 .substance unfit to be used (as has sometimes been done) in the 

 reduction of metals, when it is wished to obtain them pure, and 

 not at all sulphuretted." — (Aimales de Chimie.) 



}, Miscellaneous. 



3. Alkaline, digestive Lozenges. 

 M. d'A.rcet recommends the following formula for the prepa- 

 ration of anti-acid lozenges, for dyspeptic patients, instead of 

 !those commonly prepared with magnesia, the frequent use of 

 which, he feared, might lead to the formation of urinary calculi. 

 M. d'Arcet states that he has found great reUef from these 

 lozenges in his own case, and that they are now in general 

 •request in Paris, Lyons, 8u;. 



T^ Bicarbonate of soda, dry, and in fine powder ^i 



White sugar, in fine powder B'lss 



Mucilage of gum tragacanth, prepared with water .... q s. 

 Essential oil of mint {menthe) pure, and recently pre- 

 pared ""l V. 



The bicarbonate of soda and the sugar are put into a very dry 

 bottle, and well mixed by agitation ; the mixlure is then trans- 

 ferred to a marble mortar or slab, and rubbed up with the muci- 

 lage and essential oil, till the whole is thoroughly incorporated 

 into a paste, and then divided into lozenges, which, when dry, 



• For an account of the Highgate resin, sec AmaU of PliUosophy, vol. ii. p. 9. 



