The only means of discovering alogisms in thought is concrete dialectical analysis of reality reflected in the utterance.

New England + -er → New Englander

[…] he found Mr. Poulter, with a fixed and earnest eye, wasting the perfections of his sword-exercise on probably observant but inappreciative rats.

The castled crag of Drachenfels Frowns o’er the wide and winding Rhine Whose breast of waters broadly swells Between the banks which bear the vine And hills all rich with blossomed trees And fields which promise corn and wine And scatter’d cities crowning these Whose far white walls along them shine, Have strew’d a scene, which I should see With double joy wert thou with mo.