Sentence:  It would have been too serious a task to verify his numerous citations in our very careful reading for the present notice; but we are bound to say that, observing his <WSD>discredit</WSD> of some of the passages which he quotes from a contemporary American writer, and struck ourselves with the apparent inexactness of the statements in teste extracts (pp. 579, 616, 647), we were led to compare his citations, and, to our surprise, we find them incorrect and even garbled, and in one place where he had queried (thus (?)) the fact, we were surprised to find the doubt pertained to one of his own interpolations in the extracts. 
Meaning of the word marked with <WSD> tags:  Discrediting or disbelieving.