386 ODOROGRAPHIA. 



candy or a lozenge, possessing in a condensed form the exliilarating 

 properties and medicinal virtues of true cofiee ; easily portable, 

 and convenient under many circumstances for making an extem- 

 poraneous cup of the cherished beverage. Much of the so-called 

 " Essence of coffee " now vended is simply treacle and burnt sugar 

 flavoured with coffee. AVhen taken in excess, coffee exercises a 

 very baneful effect on the system, and its abuse becomes a habit 

 very ditticult to break off; but in moderation it exercises a power- 

 fully beneficial influence, retarding the waste of the tissues of the 

 body, exciting the brain to increased activity, exhilarating without 

 intoxicating, and to a great extent neutralising the narcotic effect 

 of tobacco smoke. Chicory produces none of these physiological 

 effects, but possesses medicinal properties which are not desirable 

 in an article of diet. 



Eupione. A hydrocarbon discovered by Reichenbach.* It 

 forms the chief portion of the light oil of wood-tar, and is found 

 in great abundance in coal-tar. It is also produced by the dry 

 distillation of many organic bodies, such as fixed oils, caoutchouc, 

 resin, bones, &c. It is found most abundantly in rectified bone- 

 oil and in the oils obtained by the dry distillation of rape seed and 

 hemp seed. According to Heesef it does not exist in the crude 

 empyreumatic oils obtained from these several sources, but is 

 produced in the process of purifying them by the action of 

 sulphuric acid. 



To prepare it from rectified bone oil, the oil is mixed with ^ 

 of its weight of oil of vitriol ; the lighter and clearer liquid which 

 rises to the surface is taken off and distilled with an equal weight 

 of sulphuric acid and a small quantity of nitre ; the distillate is 

 again distilled with sulphuric acid, then washed with aqueous 

 potash and with water, and after rectification is dried under the 

 air pump and treated with potassium as long as the metal shows 

 signs of oxidation. 



It consists essentially, according to Frankland, of hydride of 

 amyl, Cg Hj^o. It is a colourless, extremely mobile liquid, having 

 a very low refracting power. It is tasteless, but has an agreeable 

 odour, like that of some flowers. Its sp. gr. is 0-65 at 20^ C. It 

 expands very much when heated ; 100 vols, at oO'^ C. expanding to 



* Ann. Chem. Pharm., xiii., p. 217. 

 t Ann. Chem. Pharm., xxiii., p. 247. 



