This section is from the book "Alcohol, Its Production, Properties, Chemistry, And Industrial Applications", by Charles Simmonds. Also available from Amazon: Alcohol: Its Production, Properties, Chemistry, And Industrial Applications.
The methylated spirit for ordinary use is prepared by adding 5 litres of wood naphtha and 1/2 a litre of pyridine bases to every 100 litres of alcohol. For some years phenol-phthalein was included as a denaturant, and the wood naphtha was in smaller proportion (viz., 2 per cent.), but this has now been replaced by the formula given above.
For making varnishes and mercury fulminate the denaturing agent is 05 per cent. of turpentine. Specially-denatured spirit is also allowed in the making of ether, vinegar, and solutions of shellac.
Very small quantities of pure alcohol are used for scientific purposes free of duty, under certain conditions.