13S On a new Famish, for I Food. 



Water does not dissolve birdlime, but merely takes up the 

 mucilage, extractive matter, and acetic acid, which this sub- 

 sjtance contains. 



Alkalies dissolve it, and when concentrated they convert 

 it into a true soap. 



Weak acids soi'ten, and in part dissolve birdlime. 



The concentrated sulphuric acid blackens and chars it. 



Nitric acid communicates to it a yellow colour, and con- 

 verts it partly into the oxalic and malic acids, and partly into 

 Tcsin and wax. 



Tlie oxynuiriatic acid renders it white and solid, forminj^ 

 oxygenated birdlime. 



Alcohol has little action on birdlime j it merely dissolves 

 the resin and takes up the acid. 



Lastly, Sulphuric ether diisolves it entirely. 



Birdlime, therciore, difTers from glue iu the following par- 

 ticulars : 



1, It contains a quantity of free acetous acid. 



3. It has very little of an animal nature. 



3. Both mucilage and extractive matter may be obtained 

 from it. 



4. By the action of the nitric acid it yields a large quan- 

 tity of resin. 



5. It is soluble in ether. 



XXni. Oti a new Famish for JFood. Bif M. Par- 



MENTIKU *. 



X KE apothecary of the French military hospital at Genes, 

 M. Bompoix, has sent me some coft'ee-cups, the chief merit 

 of which appeared at first to arise from their lightness, but 

 afterwards I discovered that they were still far superior on 

 account of the varnish which covered them. This varnish 

 enjovs a great reputation, and the composition of it is kept 

 a profound secret in that country; I therefore charged 

 7*1. Bompoix to use every exertion to discover the recipe 

 from wiiich it is made; and he at last obtained it by means 

 of one of his pupils, whose intimacy with the master of the 



* lYom ylnnaks Je C!'i>iu(\ tome Ivi. 



manufiiciory 



