This paper discusses Mapping Temporal Relations of Discussions Software (MTRDS), a Web-based application that visually represents the temporal relations of online discussions. MTRDS was used to observe interaction characteristics of three online discussions. In addition, the research employed the Practical Inquiry Model to identify indices of cognitive presence in discussions. MTRDS made the topology of discussions apparent as well as individual user communication patterns. The results of this inquiry appear encouraging in terms of the software's utility. The three discussions analyzed did not exhibit the four phases of the Practical Inquiry Model. Most discussion occurred at a questioning or elaboration level. However, two discussions showed evidence of higher cognitive processing in terms of students synthesizing and integrating ideas.