I first thought the mention of the Scopes trial on page 36 "...the consternation which descended upon the questioner was only equaled in that household by her reception of the news of the Scopes trial in distant Tennessee." was merely a contextual marker to tell us that it was now 1925.
Interestingly though, the Scopes trial was a bit of a farce (I knew about Scopes in name only "Clarence Darrow for the defense.")
From the Wikipedia article on the Scopes Trial:
At issue was the Butler Act, which had been passed a few months earlier. In its preface, it described itself as "An act prohibiting the teaching of the Evolution Theory in all the Universities, Normals and all other public schools of Tennessee, which are supported in whole or in part by the public school funds of the State, and to provide penalties for the violations thereof."
The American Civil Liberties Union had offered to defend anyone accused of teaching evolution in defiance of the law. The leaders of Dayton, Tennessee, then a town of less than 3,000, thought that the controversy of such a trial would put Dayton on the map. They asked a 24-year-old science teacher and athletic coach named John T. Scopes, who agreed. The original prosecutors were his friends Grant and Sue Hicks.
I don't mean to say this is significant in terms of the overall novel, but just one more fun layer of allusions that WG has dropped in to keep us busy (reading other things than his novel). :)
p.s. I am now kicking myself, because I recently boxed up my copy of Berger's "Way of Seeing."