Great Britain was one of the first countries to sanction the employment of denatured alcohol free of duty for industrial uses.

The high price of duty-paid spirit was found to he interfering seriously with trade, partly by compelling manufacturers to resort to inferior substitutes, and partly, where such substitutes were not available, by making it difficult to compete with manufacturers on the Continent where the duty was inconsiderable or where, as in France, the pure alcohol was allowed to be used free of duty. The matter was brought to a head in the year 1853, when the patentee of a lubricant intended as a substitute for sperm oil applied to the Treasury for permission to receive alcohol free of duty for use in making the lubricant. This application led to an extensive series of experiments,. carried out in the Inland Revenue Laboratory under the auspices of its chief, Mr. Geo. Phillips, in order to ascertain whether it would be practicable to allow the use of alcohol free of duty for manufacturing purposes, without endangering the revenue derived from potable spirits. The outcome of these experiments was the proposal to add crude wood naphtha to spirits of wine. This addition, it was considered, would suffice to prevent abuse of the privilege, if granted. The suggestion was referred to Profs. Graham, Hoffmann, and Redwood, the well-known chemists of their day, who reported in favour of a mixture of 10 per cent. of wood naphtha with spirits of wine being accepted as a denatured alcohol which could be used free of duty without serious detriment to the revenue from potable spirits.

Such a mixture, termed "methylated spirits," was legalised in 1855 by the Act 18 & 19 Vict., cap. 38. This measure was found very beneficial in its operation as regards both industry and scientific research. It also lessened the practice of illicit distillation of spirits, which has been carried on from time immemorial in various parts of the United Kingdom, and even yet, especially in Ireland, and to some extent in Scotland, is by no means extinct, in spite of the fact that exceptional legislation has been enacted for those countries.1 Much of the alcohol formerly produced by illicit distillation was not used for drinking, but was sold to varnish makers and other manufacturers of goods in which the use of alcohol was required: this market was practically cut off by the passing of the Act above-mentioned, and the consequent production of a legal untaxed alcohol.

Down to 1861 this "methylated spirit" could be used duty free for manufacturing purposes only. From 1861 to 1891 it could be used for any purpose other than consumption as a beverage or a medicine, but if used in large quantities, as for manufacturing operations, it could not be purchased from a retailer of methylated spirit, but only from a methylator, and the user was subject to Excise supervision.

1 In the year 1914 there were 1,016 detections and seizures of illicit dis-tilling-plant and materials in Ireland, and 2 in Scotland.

In 1891, however, the use of this spirit (which subsequently came to be described as "ordinary" methylated spirit) was confined to manufacturing purposes. For domestic and general requirements a "mineralised" methylated spirit was brought into use; this consisted of the above "ordinary" spirit with an addition of 0 375 per cent. of mineral naphtha (petroleum of a certain character: see p.312 ).

This "mineralised" methylated spirit has remained in use up to the present time, but in the year 1906 the "ordinary" spirit was modified in composition as a result of the recommendations of the Departmental Committee on Industrial Alcohol.1 It was made cheaper and purer by the reduction of the proportion of wood-naphtha from 10 per cent. to 5 per cent., and by the granting of a rebate to compensate for the estimated enhancement of the cost of production due to Excise supervision. The amount of this rebate at the present time is 3d. per proof gallon of spirits methylated.

In the year 1902, however, an alternative to the use of methylated spirit was opened to manufacturers. Under the provisions of the Revenue Act, 1902, alcohol may be sanctioned for use free of duty in arts or manufactures after being subjected to some special process of denaturing, more appropriate to the particular industry, in cases where methylated spirit is "unsuitable or detrimental." Possibly, even, the alcohol could be used in a pure state, should the circumstances be held by the Commissioners of Customs and Excise to require it.

At the present time, therefore, the following varieties of alcohol may, so far as the provisions of the law are concerned, be used free of duty in the United Kingdom for industrial purposes: -

(1) Mineralised methylated spirit.

(2) Industrial methylated spirit.

(3) Alcohol specially denatured.

(4) Alcohol not denatured.

We proceed to describe these in some detail, adding a few notes as to the chief conditions under which each variety may be sanctioned for use.