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Excerpt from An Experimental Study of Speed and Other Factors in "Racial" Differences There is ample evidence that lack of familiarity with the English language contributes to the difficulty of intelligence tests for children of foreign white groups, although the esti mate as to the amount of the contribution varies considerably. 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.

Dr. Jose A. Valciukas, in Foundations of Environmental and Occupational Neurotoxicology, has written a thorough, lively, and educational study on toxic substances and their effects. Written in a manner that is accessible to both professionals and non-professionals, Dr. Valciukas explains how health and human behavior may be adversely affected by neurotoxins. He introduces his study with a history of environmental and occupational neurotoxicology.