The studies found in this book are the record of a failure, the failure of facts to sustain a preconceived theory. Bonds have certain attributes. A diversification of common stocks has its own attributes, which differs from bonds. Each class of investment has its useful purpose and its proper place in any investment plan. A clearer understanding of their differing attributes may help to determine the relative proportion of each of these two classes of securities which will best serve the investment requirements and purposes of each investor.