Apologies for the inconvenience, but it seems there was an error with the document you were referring to. To determine the author's attitudes and feelings, we would typically look at their choice of words, sentence structure, imagery, and the detail he/she includes regarding the subject. However, in this case, the document is not accessible or readable.

If you were referring to the speech "What to the Slave is the Fourth of July?" by Frederick Douglass, I can tell you that Douglass, a former slave himself, deep emotion and bias regarding the topic. His attitude is critical and sorrowful of the hypocrisy of a nation celebrating freedom and independence while millions are enslaved. His diction uses strong, hard-hitting words, his syntax often includes rhetorical questions exclamatory statements, and his imagery draws stark contrasts between the experiences of the enslaved people and the free Americans celebrating Independence Day. If one were to read the passage aloud in the author's stead, it might require a firm and passionate tone reflecting the author's indignation and fervor for the subject matter.

Please correct or provide more information if my assumption about the document is not correct.