Excerpt from Spectrophotoelectrical Sensitivity of Proustite The samples were exposed to thermal radiation stimuli extend ing from to 2 u. The greatest photoelectrical activity occurs in the region of the spectrum (o.5u to o.7, u) where there is a rapid decrease in Spectral absorption. No photoelectric reaction was observed for wave lengths greater than o.7, u. 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.