Section 30A. A registered pharmacist in a city or town wherein the granting of licenses to sell all alcoholic beverages is authorized may be licensed by the local licensing authorities to sell alcoholic beverages for medicinal, mechanical or chemical purposes without a physician's prescription subject to the limitations contained in section thirty-three, the said sales to be recorded in the manner prescribed in section thirty E. Sales of alcoholic beverages hereunder shall be made only in the original sealed packages and such beverages shall not be permitted to be drunk on the premises. Sales of such beverages by a licensee hereunder shall be permitted only during such hours as sales thereof may be made by a licensee under section fifteen.