For _perfuming oils_ a metal sieve, Fig. 17, is substituted for the glass plate. Upon the sieve a piece of thick cotton cloth saturated with oil is laid, and upon this the flowers are scattered, and left there until fresh ones have to be substituted. The operation is repeated until the oil is sufficiently impregnated with aroma, when the cloth is subjected to pressure and the expressed oil filtered. [Illustration: FIG. 17.] This process is very tedious, requiring much labor and a long time for the impregnation of the fat or oil, but, notwithstanding its faults, it is still pursued to a great extent, some French firms using 3000 such frames during the season. With the apparatus, shown in Fig. 18, the process of absorption can, however, be conducted with very little expense of labor and time. It has the further advantage that the flowers do not come in direct contact with the fat, whereby a saving of the latter is effected, and it is less liable to rancidity. The apparatus consists of a tall wooden box provided with doors which can be hermetically closed. In the box are placed upon brackets a number of glass plates, _g_, so arranged one above the other that, for instance, those with uneven numbers are on the left side, leaving an open space to the right, while those with even numbers are arranged on the right side with an open space to the left. From the bottom of the box a pipe passes into a sheet-iron cylinder, _K´_, filled loosely with flowers, and provided with lateral openings, _O_ and _O´_. From the lid of the box _K_ ascends a pipe, _e_, which is connected with a small ventilating apparatus kept in motion by a clockwork and weights. This ventilator when in motion sucks a current of air through the apparatus. The air enters the cylinder _K´_ at _O_, and after ascending through the flowers and becoming impregnated with the vapors of the volatile oil enters through the opening _O´_ into the box _K_ and, in passing in the direction indicated by arrows, over the plates coated with fat, yields its aroma to them. [Illustration: FIG. 18.] Another apparatus for the same purpose, devised by Piver, is shown in Fig. 19. The fat is converted into thin macaroni-like threads and brought upon wire gauze stretched in frames. The flowers to be extracted are piled upon tinned metallic plates, and the trays containing the fat and the flowers are placed in an air-tight chamber arranged as shown in the illustration. The air in the chamber is made to circulate to and fro by the working of a bellows with which the apparatus is provided, whereby the fat is caused to absorb the odor of the flowers very rapidly and is less liable to rancidity. [Illustration: FIG. 19.] The absorption process is employed for the flowers of the jasmine (_jasminum oderatissimum_), the mignonnette (_réséda odorata_), the violet (_viola tricolor_), the tuberose (_polianthes tuberosa_), etc.