Claim is made for a process of extraction, in an English patent, in which the seeds are placed in a rotable vessel mounted on a hollow shaft divided into compartments by means of a partition. The solvent is introduced at one end of this shaft and passes into the vessel, which is then made to rotate. After the extraction the bulk of the solvent and the extracted oil pass away through an exit pipe, and steam is then introduced through the same opening as the solvent, in order to cook the seeds and expel the residual solvent. The steam and the vapors pass through perforations in a scraper fixed to the shaft and thence through connected pipes into the other compartment of the shaft, the end of which is attached to a condenser.

Silver Nitrate Test for Cottonseed Oil

Investigations of Charabout and March throw some light on the value of this test in presence of olive oil. The free-fat acids obtained from cottonseed oil by saponification were treated in accordance with the method of Milliau on a water bath with a 3 per cent solution of silver nitrate, and the brown precipitate thus formed subjected to a chemical examination. It was found to consist chiefly of a brown silver salt composed of a fat acid melting at 52° F., and congeal ing at 120° to 122° F., and of sulphide of silver. Olive oil, which contains a sulphur compound of an analogous composition, is also capable of forming a more or less distinct precipitate of a dark colored silver sulphide with nitrate of silver. It is important to bear this fact in mind when examining olive oil for cottonseed oil.