Triturate 1 drachm of ambergris with a few drachms of powdered pumice stone or glass-sand. Transfer to a bottle and macerate the mixture in 10 drachms of alcohol for a week. At last filter. Another method of preparation is to rub the ambergris (1 drachm) with small quantities of alcohol in a mortar, macerating the mixture in 10 drachms of alcohol. To make the tincture miscible with water add by degrees an equal volume of water and some pumice or glass-sand; shake frequently and filter before use Angostura Extract. - Extract one pound of bruised angostura bark by percolation with enough diluted alcohol to make 16 fluid oz. of extract, or as much extract as desired. Improve the extract by adding about 30 grains of oil of cinnamon, 20 grains of oil of cloves and 15 grains of oil of lemon, previously dissolved in about one ounce of alcohol of 95 per cent. Mix and clarify the extract with pumice, etc.