Alcohol gets to the central nervous system by passing from the blood into the cerebro-spinal fluid, and the amount which enters this fluid is strictly proportional to the amount in the blood. From experiments on animals and from observations on man, it has been found that the onset and intensity of the symptoms of intoxication are roughly dependent on the quantity of alcohol present in the circulation. Dogs and horses began to be slightly affected when the proportion reached 012 per cent.; with higher proportions, the symptoms became more marked, and profound stupor, frequently ending in death, ensued when the alcohol content of the blood rose to 0.72 per cent.2 Similarly with man, in one case of drunkenness the blood was found to contain 0153 per cent. of alcohol; and in another instance, where the intoxication was more pronounced, 0.227 per cent. was found.3 These quantities are roughly equivalent, respectively, to total doses of 3 1/2 oz. and 5 oz. for a man of 10 stone weight.

"From the evidence at present available, it may be said that any form of alcoholic liquor, weak or strong, can cause drunkenness if such a quantity of it is taken, either at once or within a short period, as will lead to the presence of alcohol in the blood to an extent greater than a certain proportion, which in the case of the average healthy adult may be put provisionally at from 015 to 02 per cent."1 The weaker the alcoholic beverage taken, the greater must be the quantity drunk before this proportion is reached; so that the use of the more dilute beverages instead of the stronger is an important safeguard against intoxication.

1 Loc. cit., p. 86.

2 Loc. cit., p. 87; quoted in Robert, "Lehrbuch der Intoxikationen," Vol. 2, p. 986. Stuttgart, 1906.

3 Schweisheimer, Deutsch. Archiv f. Klin. Med., 1913, 109, 271.

It will be noted that all these calculations of the total dose from the alcoholic concentration found in the blood depend upon the accuracy of Grehant's experimental results mentioned above.