Es ist wirklich Brach- und Neufeld, welches der Verfasser mit der Bearbeitung dieses Themas betreten und durchpflügt hat, so sonderbar auch diese Behauptung im ersten Augenblick klingen mag.

I had taught myself German out of Teach Yourself German, and I recognised several words in this sentence at once:

It is truly something and something which the something with the something of this something has something and something, so something also this something might something at first something.

I deciphered the rest of the sentence by looking up the words Brachfeld, Neufeld, Verfasser, Bearbeitung, Themas, betreten, durchpflügt, sonderbar, Behauptung, Augenblick and klingen in Langenscheidt’s German-English dictionary.