Paragraph 2 Specification for semi-liquid mineral hydrocarbon

shall be a white translucent unctuous mixture, barely fluorescent in daylight, of semi-liquid mineral hydrocarbons;

shall contain not more than 0.1 per cent. by weight of sulphated ash;

shall have an ultra-violet extinction (otherwise called absorbance) at 290 millimicrons not greater than 1.0 for a 1 centimetre layer of a solution in iso-octane containing 1 gram per litre, that is to say, $E\frac{0.1\%}{1cm.}shall\; not\; be\; greater\; than1.0$ where E=log₁₀ (Io/I) and Io and I are the intensities of the incident radiation and of the transmitted radiation respectively; and

shall comply with the tests for acidity or alkalinity and sulphur compounds given in the monograph for Liquid Paraffin in the British Pharmacopoeia 1963.