A technically efficient method for producing artificial raindrops is presented. This approach is based upon broad basic requirements to be adopted in the systems engineering for an experimental investigation on watershed hydraulics. Modular construction of the raindrop‐producing device is adopted, allowing variable time distribution and areal coverage of rainfall intensities from 0.75 to 13 in./hr. Theoretical and photographic comparisons are made for the formation and velocity determination of 0.126‐in. (3.2‐mm) drops produced through polyethylene tubes of 0.023 in. ID. Procedures and formulas are given for making such determinations under other conditions. The proposed rainfall producer provides fast response to on‐off commands and produces in the laboratory controllable simulated storms of flexible time and areal distribution patterns.

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To the average layman, the distinction between opinion and attitude is artificial at best, and is neither consistent nor logically defensible. For many purposes one need not distinguish between the two. However, when assessing opinion and attitude the disparity becomes quite evident. Opinion surveys are characteristically concerned with replies to specific questions which need not be related. The responses are kept separately as opposed to being combined into a total score. Attitude scales, on the other hand, typically yield a total score indicating both a direction and intensity of an individual's feelings, thoughts, and predispositions to act toward a given concept. Further, in the construction of an attitude scale, the different statements are designed to measure a single attitude or unidimensional variable. The Likert method of constructing attitude measuring instruments requires a large number of judges to indicate their own attitudes by responding to statements thought to pertain to an attitude in question. Five possible responses are provided for each item. The procedure for construction of a Thurstone type scale utilizes the Law of Categorical Judgment as a basis. Statements are obtained and analyzed for the various categories and in final form, the attitude scale is presented to the respondent who indicates statements with which he agrees or disagrees.

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