What does he has erected a multitude of New Offices and sent hither swarms of Officers to harass our people and eat out their substance mean?

The phrase refers to the establishment of numerous government offices and the deployment of many officials to oversee and control the population. This action is perceived as oppressive, with officials "harassing" the people and exploiting their resources, leading to a sense of exploitation and suffering among the populace. It reflects a broader criticism of excessive government authority and the burden it places on citizens.