The use of denatured alcohol free of duty was first allowed in 1879, the system of denaturing being that followed in Great Britain at that time. In 1887, however, different regulations came into force.

1 Industrial Alcohol Committee's Minutes of Evidence, Appendix IV; Calvet, "Alcools," pp. 32-40.

The denaturing is either "complete" - i.e., such as is deemed sufficient to make the spirit undrinkable, or "incomplete " - i.e., such as requires the employment of other means to prevent the improper use of such spirit.

The general denaturing agent for " complete " denaturing consists of 4 parts of wood naphtha and 1 part of pyridine bases, to each litre of which mixture may be added 50 grams of lavender oil or rosemary oil to mask the odour of the pyridine bases. This general denaturant is used in the proportion of 2 1/2 litres to each hectolitre of alcohol.

This German methylated spirit therefore contains 2 per cent. of wood naphtha, and 0 5 per cent. of pyridine bases, with optionally 0125 per cent. of lavender oil or rosemary oil.

For use in motors, alcohol may also be completely denatured by the addition of l 1/4 litres of the "general" denaturing agent and 1/4 litre of a solution of methyl violet dye, together with from 2 to 20 litres of benzol to every 100 litres of alcohol.

The ordinary " completely denatured' spirit is intended for sale by retail, and is used for cleansing, burning, and general purposes, much in the same way as British " mineralised " methylated spirit is employed.

For general use on a large scale for industrial and manufacturing processes, alcohol denatured with wood naphtha only is sanctioned. This "wood-spirit-denatured" alcohol is a mixture of 5 litres of wood naphtha with 100 litres of alcohol of strength not less than 90°. It corresponds approximately with the British ' industrial methylated spirit."

Where this "wood-spirit-denatured" alcohol, or the ordinary "completely denatured" alcohol, is unsuitable for any particular manufacture, special denaturing agents may be allowed for "incomplete" denaturing, which is carried out only at the factories where the alcohol is to be used. The following substances are used, the quantities stated being for 100 litres of spirit at 100°.

(A) Industrial Uses Of All Kinds

Five litres of wood spirit, or 05 litre of pyridine bases.

(B) Brewers' Varnish And Similar Substances

Twenty litres of a shellac solution (1 part by weight of shellac in 2 parts by weight of spirit at not less than 90°).

(C) Celluloid And Pegamoid

One kilo, of camphor, or 2 litres of turpentine, or 1/2 litre of benzol.

(d) For all the following articles: -

(1) Ether; (2) ethyl sulphates; (3) agaricin, podophyllin, scammony, guaiacum, and jalap resins, as well as other resins and gum resins; (4) aldehyde and paraldehyde; (5) white lead and acetate of lead; (6) ethyl chloride, bromide, and iodide; (7) photographic paper and dry plates, and photo-emulsions; (8) chloral hydrate; (9) electrodes for storage batteries; (10) acetic ether; (11) glucosides; (12) rubber preparations; (13) collodion, and silver bromide, chloride, and iodide emulsions of collodion; (14) pan-creatin, alkaloids, santonin, tannin, salicylic acid and its salts; (15) coal tar colours, including substances used in obtaining them, and intermediate products; and (16) chemical preparations (not otherwise named) which do not retain any alcohol when finished (except formic, valerianic, and butyric esters): -

10 litres of ether, or 1 litre of benzol, or 05 ,, turpentine, or 0 025 ,, animal oil.

Collodion for sale must contain at least 1 per cent, of gun cotton. Ether and acetic ether are only allowed to be made from duty-free alcohol if they are to be exported, or used at home for certain specified purposes.

(E) For Making Chloroform

Three hundred grams of chloro form.

(F) Vinegar

Specified quantities of vinegar containing 3, 4, 6, 8, 10, or 12 per cent. of acetic acid, with certain proportions of water, beer, or wine.

(G) Inks, Sealing Wax, And Stamping Inks

0.5 Litre of turpentine, or 0025 litre of animal oil.

(h) Bedstead enamels, brewers' varnish, as well as for use in incandescent lamps, for finishing silk ribbons, and for cleansing jewellery, etc., 05 litre of turpentine.

(I) Iodoform

Two hundred grams of iodoform.

(K) Varnishes And Polishes Of All Kinds

Two litres of wood spirit and 2 litres of petroleum benzine; or 0 5 litre of turpentine. If intended for sale, the varnishes and polishes must contain at least 10 per cent, of shellac or other resin.

(L) Medical, Botanical, And Zoological Preparations, For Educational Purposes

One litre of commercially pure methyl alcohol and 1 litre of petroleum benzine.

(M) Soap-Making

One kilo. of castor oil and 400 c.c. of soda lye.

(N) Lanolin

Five litres of petroleum benzine.

The use of alcohol not denatured is only allowed in certain hospitals, asylums, and public scientific institutions and for making explosives, chiefly in Government factories. " For all other purposes, without exception, duty paid spirit must be used, unless the spirit be subjected to some authorised process of denaturing prior to use. The German system, while designed on liberal and comprehensive lines, is rigidly enforced, and allows of no exceptions in practice to the rules as laid down."1