Excerpt from Publications of the Washburn Observatory of the University of Wisconsin, Vol. 10: Part 1, Observations of Double Stars A discussion of the probable errors furnished by the same data shows that for all distances less than 60 the probable error of a single estimate of distance may be assumed constant and equal to For distances less than half a second, there fore, the estimates and the measurements possess very approximately the same degree of precision. At greater distances the probable error of the estimates increases very rapidly and they are of little vale. In the printed observations estimated distances are indicated by the letters est. To the printed numbers corrections taken from the above table have been applied and the corrected values included in the annual mean values which follow the observations. I am, however, by no means certain that the corrections thus applied have improved the estimated distances. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.