Definition of "soberer"

I was once very mischievous—I am not so now, age is a sad soberer of frolic fancies […]

1831, James Athearn Jones, chapter 7, in Haverhill; or, Memoirs of an Officer in the Army of Wolfe‎, volume 3, London: T.&W. Boone, page 165

[…] business, as we know, is the great soberer of theorists, no matter on what side they theorize.

1901, R. B. Cunninghame Graham, chapter 10, in A Vanished Arcadia: Being Some Account of the Jesuits in Paraguay, 1607 to 1767‎, London: Heinemann, page 278

[…] love is an intoxicant, marriage the most effective of soberers.

1914, Robert W. Service, The Pretender: A Story of the Latin Quarter‎, New York: A.L. Burt, Book 2, Chapter 1, p. 103

One evening I stayed with him very late to celebrate the birthday of his favorite actress, and for once he was slightly the worse for liquor. […] We drove off together, arranging that I should drop him at his flat and drive on to my house. When we reached Haymarket I suggested that we should stop at one of the all-night chemists and buy him one of the mixtures known as “soberers.”

1923, Herbert Vivian, chapter 8, in Myself Not Least, Being the Personal Reminiscences of X‎, New York: H. Holt, page 136