xxxvi 
EXAMPLES TO THE THIRD SERIES. 
In other cases it will be more convenient to find the scantlings by 
the table page xxxviii. 
The DEPTH is the greatest side ; the breadth, the least side of the 
scantling. 
P is the pressure in lbs. or cwts. in the direction of the depth. 
D, the deflection in inches or parts of an inch. 
p and denote the relative pressures as described in the Explana- 
tion to the diagrams. 
The least divided by the greatest pressure determines the table by 
which the scantUngs are found, thus : — 
If -y or = -le, the Scantlings are found by Table I. ; 
If or — -25, the Scantlings are found by Table II. ; 
and so on. 
In the following Examples, the scantlings are those of Red Pine. 
The scanthngs of other kinds of timber are found by the Table of Con- 
stants, No. 3, p. 96. 
EXAMPLES TO THE THIRD SERIES OF TABLES. 
Example 18. — Required the Scantling for any given length of the 
Brest-summer Q, Fig. 5, upon the following data, viz. : 
Centre of gravity G in the middle of AC ; BC = i AB ; 
Weight of AC for one foot in length of Q=1225 cwts.; 
Pressure uniform ; the deflection to be as given by the table. 
The diagonal Ec, and the sides ca, Eb, of the parallelogram Each, axe 
equ> 1. 
Ec = ca = p = q. The scant ings are gWer. by Table VI. 
The pressure upon each foot in length being 12-25 cwts. ; the scant- 
lings are given by Col. XII. p. 120. 
If the length be 9 feet, the scantling is 10-07 X 10-07. 
If the length be 10 feet, the scantling is 10-89 X 10-89. 
Deflections each way, -7?^ of an inch to the foot. 
Breaking weight, upwards of 8 times the pressure upon the brest- 
summer. 
