The tone of the essay "A Modest Proposal" on a literal level is observant and objective. Throughout the essay, Swift shows the readers what he had observe of the poor people in an objective manner. Hence the observant and objective tone. In a satirical level, it denotes a pleading tone. Swift is proposing a solution to what he had observed and therefore pleaded with the people who can carry out his proposal.
The tone of "A Modest Proposal" is Shocking. Even the literal statements are shocking in that there are so many poor and hungry children. But then it's also shocking at the satirical level because of his proposed solution of killing and eating the children and going so far to make it appear like a valid idea , with calculations of how much money could be made.