LETTERS To the Editor: I call attention of your readers to a simple method for the laying out of sites for bonds on spherical atoms. One simply draws a circle of the same size as the atom and lays out the desired angle with a protractor from the center of the circle. The desired distance is picked up with a compass or dividers from the points of intersection of the angle with the circumference and transferred to the ball. I n case one has no dividers, pinholes in a strip of any flexible material will suffice to transfer distances. The most frequently encountered angles are 90°, 109' 28', 120°, and 180°, or small distortions of these. For the more obtuse angles it is easier to transfer distances if the divider points are bent or if flexible strips are used. This method is somewhat different from that given by Mrs. Katherine Hoffman, THIS JOURNAL, 37, 637 (1960). WILBURL. BAKER JACKSONVILLE UNIVERSITY Jac~soNvr~LE. FLORIDA
Volume 38, Number 10, October 1961
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