402 Miscellaneous Intelligence. 



5. That this oil, as well as the acid accompanying it in infusions 

 of the plants, is precipitated by acetate of lead, from which preci- 

 pitate it cannot be separated by sulphuretted hydrogen. 



6. That, nevertheless, this same oil may be separated from the 

 sulphuret of lead by means of boiling alcohol, but that it remains 

 combined with sulphur. — Jour, de Phar. 1824, 424, 



27. Preservation of Red Cabbage Colour. — Digest the leaves of 

 the cabbage in warm alcohol; distil off the alcohol from the 

 coloured solution obtained, and evaporate the remainder by a 

 gentle heat until reduced to a syrup. This will keep in closely 

 stopped phials for years. When required for use, a little of it 

 should be added to so much water as will give a test liquor of 

 proper depth of colour. Test papers may be prepared from the 

 alcoholic solution. — Amer. Jour, of Science. 



28. Use of Elderberries as a Chemical Test. — ^Take a quantity of 

 picked ripe elderberries, bruise them, and press the juice into a 

 clean well-tinned vessel, add a fourth its weight of alcohol, and 

 evaporate to one half; allow it to cool for ten or twelve minutes, 

 add an equal bulk of alcohol, and strain the liquor through a fine 

 cotton cloth from the precipitate which will form. The filtered 

 liquor, now of a beautiful violet colour, is ready for use. 



As trials of its sensibility, a drop of the tincture was added to a 

 pint of rain water, the solution was so dilute that no blue colour 

 could be perceived; but a single drop of sulphuric acid produced 

 a decided red colour : a minute quantity of alkali was then added, 

 which immediately changed the colour to a bright green. If only 

 sufficient alkali be added to neutralize the acid, the original blue 

 or violet colour is restored. This test, besides being very delicate, 

 has the important advantage of keeping unaltered during the hottest 

 season of the year. The species from which the above liquor was 

 made was the Sambucus Canadensis ; but it is probable that the 

 juice of the common elderberry will answer the same purpose. — 

 Ann. of New York Lyceum. 



29. Bleaching of Sponge, hj M. Vogel. — Chlorine rather increases 

 than diminishes the colour of sponge. Sulphurous vapours do not 

 act on it sufficiently. The sponges must first be soaked for several 

 days in cold water, being frequently squeezed until the water ceases 

 to be coloured, or rendered turbid by it. The water dissolves mu- 

 riates, sulphates, and a brown animal matter insoluble in alcohol. 

 They should then be washed in hot water; this removes hydriodate 

 of potash from them, and if the washing-water be concentrated and 

 moistened with strong sulphuric acid, it will render paper, moistened 

 with solution of starch, of a blue colour ; thus shewing the presence 

 of iodine in sponges without burning them. When the sponges 

 contain calcareous concretions, they are best removed by leaving 



