30. A person who intends to have analysed or otherwise examined a sample referred to in section 28 or a sample sold or surrendered under section 29, as the case may be, shall- (1) forthwith notify in writing his intention to the person who sold or surrendered the sample; (2) divide the sample into three parts, and mark, seal or fasten each part in such manner as may be prescribed in presence of the person selling or surrendering the sample; (3) (a) in the case of a sample purchased, offer one part to the person who sold the sample, or (b) in the case of a sample surrendered, despatched by registered post one part to the consignor whose name and address appear on the container of the article, ingredient or substance sampled, together with a notice of the intention to have the sample analysed or otherwise examined or, if no such name and address appear thereon, retain the aforementioned part;(4) retain one part for purposes of future comparison; and(5) thereafter submit within seven days one part to the public analyst appointed for the area in which the sample was sold or surrendered.