This report offers a data set that we prepared to explore the allometric relations among mechanical power, speed, and mass of systems - animals and manmade systems - that move themselves via terrestrial locomotion. The data were extracted from widely available open sources. The types of systems include animals of widely different scales (such as cockroaches, crabs, quail, humans, dogs, and horses), and artificial, manmade systems such as all-terrain vehicles, trucks, tanks, and robots. The records in the data sets cover the systems mass, speed, and mechanical motive power. The report includes the data, notes on the sources of the data, and a brief example of possible uses of the data.