Archaeologists and paleontologists both frequently need to precisely establish the positions of some or all of the specimens within a deposit which is being excavated. If all of the artifacts or bones ore arranged in a single flat-lying layer, careful drawings or photographs may suffice to locate them. If the deposit, however, is more than one specimen thick, vertical as well as horizontal relationships become important, and a more accurate system of positional measurements is usually needed. For maximum accuracy over fairly large distances, no commonly available system can surpass careful plane table mapping. However, if the deposit is a large one, perhaps containing thousands of specimens, and one wishes to chart the position of nearly every object in the deposit (as frequently is the case with a site subjected to taphonomic study), complications arise. Because the plane table measurements require the cooperation of at least two workers, this method may not be the best for the average project; few field crews have sufficient personnel to be able to spare some to act as surveyor’s helpers. Fortunately, a few other measuring systems exist which, while not producing results as accurate as the transit and plane table system, are nevertheless sufficiently accurate for most purposes. The main strength of these other systems is that they can be set up and operated by a single worker. This paper describes one such system and a new device we developed in order to make the taking of some measurements easier and more accurate. Although the device and measuring system were both developed with the needs of one specific vertebrate site in mind (the Los Angeles County Museum excavations at Rancho La Brea), we believe that with minor modifications they should be useful in any situation which requires a large number of positional measurements in the field.