rO RESINOUS SECRETIOVS. 



Bot. f. 1581, and some plants allied to it, the emulsion 

 is orange-coloured. (7) 



The more refined and volatile secretions of a resinous 

 nature are called Essential Oils, and are often higMj 

 aromatic and odoriferous. One of the most exquisite 

 of these is afforded by the Cinniimon bark. Tl'.ey exist 

 in the highest perfection in the perfumed effluvia of 

 flowers, some of which, capable of combination, with 

 spirituous fluids, are obtainable by distillation, as that 

 of the Lavender and Rose ; while the essential oil of 

 the Jasmine is best procured by immersing the flowers 

 in expressed oil which imbibes and retains their fra- 

 grance. Such Expressed or Gross Oils, as they are 

 called, to distinguish them from essential oils obtained 

 by distillation, are chiefly found in the seeds of plants. 

 In the pulp of the Olive indeed they occur in the form 

 of an emulsion, mixed with watery and bitter fluids, from 

 which the oil easily separates by its superior lightness. 

 These expressed oils are not soluble in spirits or water, 



(7) [The resinous juice, known in the northern states by the 

 name of Fir balsajn., is a spontiineous exudation from the Pinus 

 Balsamea, retained in little sacs or vesicles upon the bark. 

 Turpentine is obtained in great quantities from the North 

 American Pines, particularly Pinus Palustris. by incisions or 

 excavations in the trunk. When Turpentine is distilled, the Oil 

 of Turpentine comes over, and Resin remains behind. Tar is 

 obtained from the resinous trees by a slow combustion of their 

 wood. 



Wax is a vegetable product. It exists on the surface of 

 leaves, and probably in the pollen of flowers. It is obtained in 

 large quantities from the berries of Mijrica Ccri/era, Bayberry 

 bush, or Wax Myrtle ; Ijy boiliny; the berries in water until the 

 wax melts and lloais upon the surlacc.] 



