384 Scientific Notices — Chemistry. [Nov. 



Article XII. 

 SCIENTIFIC NOTICES. 



Chemistry. 

 1 . Juice of Elder Berries as a Test. 



The juice of the elder berries seems to possess important 

 properties as a delicate reagent. The following process was 

 employed : — 



Take any quantity of the ripe berries, picked clean from the 

 stalks, and after having bruised them, press the juice into a 

 clean well-tinned vessel. Add a fourth part of its weight of 

 alcohol, and evaporate the mixture to one-half. Remove it from 

 the fire for ten or twelve minutes, and add as much alcohol as 

 you have of concentrated juice. A copious precipitation of the 

 parenchymatous and gummy parts will take place, which will 

 permit the liquor to be strained with ease through a fine cotton 

 cloth. 



The filtered liquor is now fit for use. It consists of the sac- 

 charine and colouring principles of the berries, in solution with 

 alcohol and water. It is of a beautiful violet colour. In order 

 to ascertain its utility as a test of acids and alkalies, the follow- 

 ing experiments were made : — 



To one pint of rain water a single drop of the tincture of elder 

 berries was added. The blue colour was too pale to be per- 

 ceived ; but the addition of a single drop of sulphuric acid pro- 

 duced a decided red colour. 



To the liquor employed in the last experiment, a minute 

 quantity of alkali was added, when it immediately changed to a 

 bright lively green. If a quantity barely sufficient to neutralize 

 the acid be employed, the original blue or violet colour is 

 restored ; hence this test possesses all the delicacy of the tinc- 

 ture of litmus, or blue cabbage, and has this additional valuable 

 property of keeping unaltered, during the hottest season of the 

 year. The species tried as above was the Sarnbiiciis canadensis; 

 the juice of the common elder berry (Sambucus nigra) will 

 probably answer as well. — (Annals of the Lyceum of Nat. Hist. 

 ol'Xew York.) 



2. Volatility of the Salts of some of the Vegetable Alkalies. 



Ferrari states that all the salts of Strychnia, when dissolved 

 in water, are volatile in temperatures below that of boiling water. 

 The volatilization is most considerable when the solution is 

 concentrated, and when it contains an excess of acid. The salts 

 which he examined were the sulphate, muriate, nitrate, and 

 acetate. He remarked also that the muriate of chinin is so vola- 

 tile that the steam which rises from its aqueous solution in a 



