"at last, after what seemed a long time—it might have been five seconds, i dare say—he sagged flabbily to his knees. his mouth slobbered. an enormous senility seemed to have settled upon him." in three to five sentences, explain the methods used by the author to create sentence fluency and rhythm in this passage.

This author uses a variety of methods to flow from one idea to the next in this passage, and to improve sentence fluidity. First, the author sets the pace of this moment by placing the reader in a moment in which the action is already happening, which is done by using the phrase "At last". Then, the author pauses, using an em-dash, to give an explanation without stopping the action of the story (considering we are curious at this point as to what is happening "at last"). The author then uses short, descriptive sentences to speed up the action, and draw the reader into the moment. 

Is there more to this?