1467. Millon's Method of Obtaining Essential Oils

1467.    Millon's Method of Obtaining Essential Oils. The flowers are placed in a percolating apparatus (see No. 41 (To obtain Tinctures by Displacement or Percolation)) and then ether or sulphide of carbon is poured over them. After leaving the flowers in contact for 15 minutes the liquid is drawn off and a fresh supply added and drawn off in a similar manner. This completely dissolves all the essential oil of the flowers, leaving them quite scentless. The liquid is next distilled, and the ether or sulphide of carbon, being volatile at a much lower temperature than the fragrant principle, is drawn over alone, and leaves a residue containing all the perfume of the flower. This residue, more or less solid, is exposed to the heat of the sun until it loses the unpleasant smell of the solvent used. No degree of natural heat is capable of altering the perfume or turning it rancid. The product has a much finer odor than essential oil prepared by any other system.

1468. Cognac Oil

1468.    Cognac Oil. Oil of cognac is prepared by dissolving the fusel oil of brandy marc in strong rectified spirit, and then adding a sufficient quantity of concentrated sulphuric acid to form a sulphate; alcohol and excess of acid are removed by washing the newly formed compound with water. To 100 pounds marc add 1/2 pound sulphuric acid; the oil is generally formed towards the end of the distillation, and is found floating in blackish drops on the surface of the distillate. According to a distinguished French chemist, this oil is a compound of potato oil and cenanthic ether.

1469. Oil of Apple

1469.    Oil of Apple. Mix cautiously 1 part fusel oil, 3 parts sulphuric acid, and 2 parts water. Dissolve 21/2 parts bichromate of potash in 41/2 parts water, introduce this* into a large tubulated retort, and gradually add the former liquid, so that the boiling continues very slowly. The distillate, which is principally valerianic acid, is saturated with carbonate of soda, and evaporated to dryness. Take of the valerianate of soda, thus formed, 11/2 parts; fusel oil, 1 part; sulphuric acid, 1 part; mix cautiously, heat by a water-bath, and mix with water; the impure valerianate of amy-loxide will separate. It is washed several times with water, then with a solution of carbonate of soda, and finally with water. This is dissolved in from 6 to 8 parts of water.

1470. Oil of Jargonelle Pear

1470.    Oil of Jargonelle Pear. This is made from the heavy fusel oil which comes over last in distillation. To purify the fusel oil, wash it with soda and water, and distill between 254° and 284° Fahr. Of this take 1 pound; glacial acetic acid, 1 pound ; sulphuric acid, 1/2 pound. Digest for some hours at 254°. The ether separates upon the addition of water, and is purified by washing with soda and water. Mixed with 1/30 part acetic ether, and 7 parts of deodorized alcohol, it gives the essence of pears.