This is a mixture of 19 volumes of "plain" spirit with 1 volume of wood naphtha. It differs, therefore, from the ' mineralised" spirit in containing no mineral naphtha, and in having only one-half the proportion of wood naphtha - 5 per cent. instead of 10 per cent. It is the variety of duty-free alcohol chiefly used in manufactures. Since it is much purer than the mineralised spirit, it is subjected to closer supervision as a check upon possible malpractices. It is not allowed to be sold by retailers; it can only be obtained from methylators, and in quantities of not less than 5 gallons at a time. Further, the user must be specifically authorised, by the Commissioners of Customs and Excise, to receive the spirit for duly approved purposes, and he cannot obtain it except upon the production of the official " requisition," which is not granted until the authority has been duly issued empowering the prospective user to receive the spirit. The chief restriction upon the purposes to which the industrial methylated spirit may be put is that it may not be used in beverages, or perfumes, or in medicines to be taken internally. It is allowed to be used, however, as a solvent in preparing medicinal extracts from crude drugs, provided all the spirit is afterwards expelled from the extracts. It is employed also for extracting and crystallising alkaloids and other solid medicinal substances, as well as for the production of ether, chloroform, chloral, and ethyl bromide, chloride, and iodide, in which the alcohol has undergone a molecular transformation, and no longer remains as alcohol in the finished product. Similarly, industrial methylated spirit may be used (under authority) in the chemical operations involved in making synthetic perfumes, but may not be present as such in perfumed spirits. Recovery of the methylated spirit by distillation from extracts, marcs, etc., is generally permitted, provided the spirit is not purifed in the process. Usually the recovered alcohol is required to be used again for the same purpose as it was originally employed for.

Medicaments intended for external use, such as soap linament and also certain hair lotions, may legally be made, under authority, with industrial methylated spirit, provided always that they are not capable of internal use, or of employment as perfumes,

The average composition of industrial methylated spirit, taking the strength as 62° over proof, may be expressed as follows: -

Industrial methylated spirit at 62° o.p.

Per cent. by volume.

Ethyl alcohol ...........................................................................

87.92

Methyl ,, ............................................................................

3.87

Ketones, calculated as acetone ...................................................

0.51

Esters, ,, methyl acetate ......................................

0.06

Unsaturated compounds, calculated as ally] alcohol ................

0.04

Basic ,, ,, pyridine .........

0.01

Water ........................................................................................

9.21

101.62

At a strength of 61° o.p. the proportion of ethyl alcohol is 87.35 per cent., and at 64° o.p. it is 89.06 per cent.