330 



Rural Architecture. 



strength of moderately seasoned white and yellow pino 

 pillars: 



Rule. Divide the square of the length in inches by the 

 square of the least thickness in inches; multiply the quo- 

 tient by .00 Jf. and to this product add 1; then divide 5,000 

 by this sum and the result is the strength in pounds per 

 square inch of area of the end of the post. Multiply this 

 result by the area of the end of the post in inches, and the 

 answer is the strength of the post in pounds. 



In applying this rule in the construction of farm build- 

 ings the timbers should not be trusted with more than one- 

 fourth to one-sixth of the theoretical load they are com- 

 puted to carry, because the theoretical results are based 

 upon averages, and there is a wide variation in the strength 

 of individual pieces. 



Table of breaking load in tons, of rectangular pillars of half 

 seasoned white or yellow pine firmly fixed and equally 

 loaded, computed from C. S. Smith's formula. 



In the application of the rule for the crushing load for 

 posts in barn building the length referred to is the greatest 

 distance between any supports which prevent the post from 

 bending. 



401. Bearings for Posts. In order that a post may carry 

 its maximum load it is important that it rests squarely 

 upon its support and that the load carried presses squarely 

 upon the post. If the ends of the post are not square or if 



