These comprise the third class of objects subject to compression (Art. 97), and include all posts which are less than ten diameters high. The resistance to compression, in this class, is ascertained to be directly in proportion to the area of cross-section of the post.

Now in Table I., column C, the ultimate resistance to crushing is given for the several kinds of materials named; from which the safe resistance per inch may be obtained by dividing it by a proper factor of safety. Having the safe resistance per inch, the resistance of any given post may be determined by multiplying it by the area of the cross-section of the post. Therefore, proceed as follows: