PREFACE. 
V 
At the foot of each page of the tables there is an explanatory exam- 
ple. The use of the work is further and fully shewn in the various 
diagrams and practical Examples which precede the tables. 
If a joist, beam, lintel, brest-summer, or purlin, uniformly loaded with 
a given weight, be assumed as a Standard by which to determine the 
scantlings of other joists, beams, lintels, brest-summers, or purlins, 
to carry a similar weight; the dimension, or one near to it, of the for- 
mer will be found in some one of the tables in the First or Third Series; 
by which table the scantlings for that and other lengths are given, to 
carry the same weight, and to have the same deflection for each foot in 
length, as the standard bearing timber so assumed. 
As'accuracy is of the utmost importance in a work of this description, 
the Author has spared no pains in carefully revising, correcting, and 
checking, in several ways, every calculation in the original manuscripts, 
and from those, the proof sheets ; both of which have been again 
minutely revised. 
BiKMINOHAM ; 
May, 185(>. 
