(23) 



tea, mate or Paraguay tea, Jersey tea and fruit juices, and 

 the alcoholic and malt beverages, as wine, beer, ale and 

 porter. In the block of cases devoted to beverages may be 

 found chocolate, which is derived from the seed of the choc- 

 olate tree (Theobroma) . The collection shows the choc- 

 olate fruits, the principal commercial varieties of the seeds, 

 unroasted and roasted, nibs of different degrees of fineness, 

 germs, cocoa-liquor, cocoa-butter, cocoa-cake, and the same 

 ground into " breakfast "-cocoa, with several varieties of con- 

 fectioners' chocolate, as put up for the market. 



Miscellaneous Specimens. Case 42. — In this case may be 

 seen the substances used in the manufacture of soap, insect 

 powders and related substances. 



Fixed and Volatile Oils. Cases 43 to 48. — The volatile 

 oils form a large series, and in their manufacture various 

 parts of the plants are used; for example, roots are used to 

 make the oils of lovage-root, elecampane and muskroot; 

 rootstocks furnish the oils of calamus, ginger, orris root and 

 wild ginger; herbage is the source of the oils of pennyroyal, 

 tansy, spearmint and peppermint; wood furnishes the ma- 

 terial to make the oils of red cedar wood and sandalwood; 

 bark is the source of the oils of birch, cinnamon and sassa- 

 fras; leaves yield the oils of hemlock, spruce, pine, cedar, 

 eucalyptus and wintergreen; flowers yield the oils of cloves, 

 lilac flower and orange flowers; fruits yield the oils of pep- 

 per, lemon, caraway and fennel; seeds furnish the oils of 

 mustard, wormseed, nutmeg and almonds; while resins give 

 us the oils of elemi, mastic, myrrh and frankincense. 



The fixed oils, at least from a commercial standpoint, are 

 less numerous than the volatile oils, and those in common use 

 are mostly derived from the fruits and seeds of plants; for 

 example, olive oil is contained in the fruit of the olive, lin- 

 seed oil is contained in the seed of the flax plant, castor oil 

 is stored up in the seed of the castor oil plant and cotton oil 

 abounds in the cotton seed. Fixed oils differ from volatile 

 oils in not completely evaporating when exposed to the air. 

 In many cases the by-products resulting during the manufac- 



