The lard is now to be washed.  This is done in small portions at a time, and is a work of much labor, which, however, is amply repaid by the result.  About a pound of the grease is now placed on a slate slab a little on the incline, a supply of good water being set to trickle over it; the surface of the grease is then constantly renewed by an operative working a muller over it, precisely as a color-maker grinds paints in oil.  In this way the water removes any traces of alum or salt, also the last traces of nitrogenous matter.  Finally, the grease, when the whole is washed in this way, is remelted, the heat being maintained enough to drive off any adhering water.  When cold it is finished.

Although purifying grease in this way is troublesome, and takes a good deal of time, yet unless done so, it is totally unfit for perfuming with flowers, because a bad grease will cost more in perfume to cover its mal odeur than the expense of thus deodorizing it.  Moreover, if lard be used that “smells of the pig,” it is next to impossible to impart to it any delicate odor; and if strongly perfumed by the addition of ottos, the unpurified grease will not keep, but quickly becomes rancid.  Under any circumstances, therefore, grease that is not perfectly inodorous is a very expensive material to use in the manufacture of pomades.

In the South and flower-growing countries, where the fine pomades are made by ENFLEURAGE, or by MACERATION[G] (see pp. 37, 38), the purification of grease for the purpose of these manufactures is of sufficient importance to become a separate trade.

The purification of beef and mutton suet is in a great measure the same as that for lard:  the greater solidity of suets requires a mechanical arrangement for washing them of a more powerful nature than can be applied by hand labor.  Mr. Ewen, who is undoubtedly the best fat-purifier in London, employs a stone roller rotating upon a circular slab; motion is given to the roller by an axle which passes through the centre of the slab, or rather stone bed, upon which the suet is placed; being higher in the centre than at the sides, the stream of water flows away after it has once passed over the suet; in other respects the treatment is the same as for lard.  These greases used by perfumers have a general title of “body,” tantamount to the French nomenclature of corps; thus we have pomades of hard corps (suet), pomades of soft corps (lard).  For making extraits, such as extrait de violette, jasmin, the pomades of hard corps are to be preferred; but when scented pomade is to be used in fabrication of unguents for the hair, pomades of soft corps are the most useful.

The method of perfuming grease by the direct process with flowers having already been described under the respective names of the flowers that impart the odor thereto, it remains now only to describe those compounds that are made from them, together with such incidental matter connected with this branch of perfumery as has not been previously mentioned.