30 FOREIGN TRADE ZONES not destined for domestic consumption. Merchandise can remain in the free zone up to four years without payment of customs duties, during which time it can be indiscriminately destined all or in part to domestic consumption or to reexportation abroad, paying duties only on that part destined for consumption. Merchandise which by its condition and character or which on account of its packing is con- sidered prejudicial or inconvenient or which may cause prejudice to other goods deposited may be refused. Certain merchandise, the prohibition on importation of which is temporary or circumstantial, can, however, be admitted to the free deposit for four years, enjoying all privileges of other merchandise except that of introduction to domestic markets. Cadiz —Repacking, assorting to facilitate commercial classification, shelling and roasting of coffee and cacao, shearing of skins and hides, wood crushing, washing and cleaning of wool, extraction of copra and other vegetable oils, and other operations that may increase the value of merchandise received without essentially changing its nature are permitted in the free zone. The last provision indicates the intention to restrict operations which change the nature of the goods. Santander. —The changing of packing of goods, the division and mixing of same so as to prepare commercial classes, hulling and toast- ing of coffee and cacao, tanning of skins, trituration of woods, cleaning of wool, extraction of oil from copra and oily seeds, and any changes that increase the value of goods without altering their nature are allowed under the supervision of the administration. These conces- sions may be extended at the discretion of the Government. Genoa.—The operations permitted in the warehouses of the free zone include storage, grading, treatment, and preparation of such products as coffee and cocoa, the bottling and canning of food prod- ucts of various kinds, and the refining of edible oils. The following goods are not accepted for storage: Salt and tobacco, now under the monopoly of the State; powders and explosives; matches, kerosene, sulphur, turpentine, tar, and alcohol; sausages, cheese, and similar goods; concealed weapons; playing cards, pocket articles, precious articles; garments, linen, manufactured in any way ready for wear; hats, neckties, handkerchiefs not in bulk, gloves, and shoes; and for- eign wines. Deteriorated goods or merchandise in process of deterio- ration will not be admitted unless accompanied by a certificate relieving the authorities from any responsibility. Leghorn.—All ordinary operations of commerce are permitted, with the exception that inflammable materials and Government monopoly goods are not admissible, and also that medicinal products are only admissible upon the presentation of a permit issued by the customs officials.