3.—(1) Subject to paragraphs (2) and (3), unless pre-packed in a securely closed container, intoxicating liquor of any of the following descriptions, that is to say, gin, rum, vodka and whiskey, shall be sold by retail for consumption on the premises at which it is sold only in a quantity of one-quarter of a gill or a multiple of one-quarter of a gill.
(2) Any such liquor shall be exempted from the requirements of this Article when it forms a constituent of a mixture of three or more liquids.
(3) Nothing in this Article shall make unlawful the sale at the express request of the buyer of any mixture of liquids containing any of those liquors in a quantity not otherwise permitted by this Article.