This paper discusses a way to merge two sorted files in place and in linear time by dividing one file into a number (O(:9IN)) of equal parts, splitting the second file into matching parts, and resequencing them inthe order A1, B1, A2, B2, .9T.9T. before finally merging them. The need for an additional workspace is avoided by using the back and then the front section of the files as workspaces (which require resorting in place as a final step.