DESCRIPTION AND USE OF THE TABLES. 
The outline of this work is described in the Preface, and the further 
description and use of the tables are shewn by the following Examples. 
THE FIRST SERIES OF TABLES, 
By which and the Table of Constants No. 1, may be found the Scant- 
lings of any description of Timber sufficient to carry a given weight, 
and to have with that weight a given deflection. 
The greatest weight upon a joist beam or lintel being ascertained or 
given, and the deflection when loaded with that weight assumed, the 
scantlings are found by the First Series of Tables. 
The weight being ascertained, if the tabular deflection be that as- 
sumed, the scantlings are given by inspection of the tables. 
If the assumed deflection be greater or less than the tabular deflec- 
w 
tion, the scantlings are found by means of the expression — , at the 
head of each table. In Ihis case it will be requisite to fix upon the 
least breaking weight of the required scantling, and then by the multi- 
pliers and weights in the table find the breaking weights of the scant- 
lings, as in Examples 4 and 6. 
w 
When the weight or the value of — falls between two of the tables, 
the depth may be found as in Example 1 . 
In the following Examples, 
W=weight in lbs., cwts., or tons ; either upon each foot in length, 
uniformly loaded, or suspended from the middle, as the case may 
be ; and 
D = deflection in inches or parts of an inch. 
If W= weight upon each foot in length, then 
D = deflection for each foot in length. 
If W= weight either uniformly loaded or suspended from the 
middle, then 
D = deflection in the middle of the scantling. 
c = constant in any column in the Tables of Constants, No. 1, 
2 and 3. 
d 
