It's not dated, but my guess would be the article was published sometime between 1918 and 1920. That's based on the rest of the notebook entries and the fact that it mentions the Central Control Board (Liquor Traffic), a body set up during WW I.
You just have to love a publication with the delightful name of the Journal of Inebriety. I wonder if it's still going?
In the current number of the Journal of Inebriety Dr. H.M. Vernon, of Oxford, has published some arresting experiments and conclusions on the subject of alcohol. Among his most important points in regard to the liquor question is the contention that beer containing only 3 per cent. of alcohol is a temperance fluid- that is to say, its dilution in relation to toxicity is so great that it is practically impossible to get intoxicated on such a beverage. The public opinion with regard to these innocuous beers is outspoken; they are not popular, while the remedy for the situation, namely, a high tax for stronger beer, would certainly meet with public opposition.
As far as Dr. Vernon is concerned personally, we must take it as proven that beer containingf 3 per cent. by volume of alcohol is a non-intoxicating fluid, for his experiments show that it would take half a working day to consume the amount needed to produce a state of intoxication. The general conclusion was reached by the experiment that the toxic effect of alcohol taken in a much diluted form is very small indeed, while the conclusion that claret has the same toxic effect as whisky when diluted to an equal alcoholic strength will come as a surprise to some, though very many unscientific people had found this out. The experiments were undertaken at the instance of the Central Control Board (Liquor Traffic).
Having cut my drinking teeth on draught Mild that just about peeped over the parapet of 3% ABV, I would disagree that you can't get plastered on beer of this strength. Just that you need to be pretty determined and have a stomach capacity of at least a gallon.