To my considerable surprise, a convenient sample of older books on my bookshelf tend to confirm the author's contention (year of publication order, all London,

To my considerable surprise, a convenient sample of older books on my bookshelf tend to confirm the author's contention (year of publication order, all London, see file names for specifics). https://dl.dropboxusercontent.com/u/8403291/typography-sample-neville-wardlock-london-1886.png https://dl.dropboxusercontent.com/u/8403291/typography-sampl... https://dl.dropboxusercontent.com/u/8403291/typography-sample-rossetti-oup-london-1913.png https://dl.dropboxusercontent.com/u/8403291/typography-sampl... https://dl.dropboxusercontent.com/u/8403291/typography-sample-ae-mcmillan-london-1920.png https://dl.dropboxusercontent.com/u/8403291/typography-sampl... https://dl.dropboxusercontent.com/u/8403291/typography-sample-brod-knopf-london-1928.png https://dl.dropboxusercontent.com/u/8403291/typography-sampl... Oxford University Press was using single space like spacing around 1950, but I have a travel book about Greece published in 1947 (George Allen Unwin) that still uses a very large space after a full stop.