VOLATILE OII.S.

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of applying heat so as to maintain a regulatedtemperature not much above 212°. On thesmall scale heat may be thus conveniently ap-plied by means of a bath of a strong Solution ofmuriate of lime, or by means of an oil-bafh,kept at a stationary temperature with the aidof a thermometer. On the large Scale heat isoften applied by means of steam under regula-ted pressure. In other Operations it is foundsufficient to hang the material within the stillin a cage or bag of fine net-work; and some-times the material is not mingled with thewater at all, but is subjected to a current ofsteam passing through it.

The best mode of collecting the oil is bymeans of the refrigeratory described in thePreface; from which the water and oil droptogether into a tall narrow vessel providedwith a lateral tube or lip near the top, andanother tube rising from the bottom to abouta quarter of an inch below the level of the for-mer. It is evident that with a receiver of thisconstruction the water will cscape by the lowertube; while the volatile oil, as it accumulates,will be discharged by the upper one, except inthe very few instances where the oil is heavierthan water.

By attending to the general principles nowexplained, Volatile oils may be readily obtain.ed of excellent quality from the flowers ofAnthemis nobilis,Lavandula vera, and