Linseed or flaxseed oil; name on barrel or container; evidence of violation.

No person, firm or corporation, either by himself or another, shall sell, offer or expose for sale, or have in his possession with intent to sell in this state any linseed oil or flaxseed oil, except under its true name, and unless each barrel, keg or can of such oil has plainly and durably painted, stamped, stenciled, labeled or marked thereon the true name of such oil in ordinary bold-faced capital letters, not less than 5 lines pica in size, together with the name and address of the manufacturer, jobber or dealer: Provided, That if the contents of the package be less than 25 gallons, the type shall not be less than 2 lines pica in size. Proof that any person, firm or corporation has or had possession of any oil or compound which is adulterated or misbranded within the meaning of this act shall be prima facie evidence that the possession thereof is in violation of this act.