DEPTH AND EXTENT OF THE GERIATRIC PROBLEM

control of both visible and invisible emissions; and legal and economic aspects. However, the material is so uneven in presentation, emphasis, and thoroughness, that it will very likely fail in its purported appeal to the general audience. For example, about 12 pages are devoted to derivations of equations that govern the applications of Stokes' Law to the behavior of particulates. A scant three pages are given to a chapter grandly entitled, "Toxicology and Epidemiology of Air Pollution." This chapter, incidentally, begins with the statement, "Toxicology is the study of poison, and epidemiology is the study of disease"-two definitions that are quite likely to turn off the public health professional. The treatment of legal and economic aspects is similarly meager, and fails to take cognizance of significant current problems in this area. MORRIS M. JOSELOW