134 
MISCELLANEOUS TABLES. 
TABLE IV. 
By which may he determined the depths of Ceiling Joists, Rafters, 
Floor Joists, Bridging Joists, &c.; the breadth being If inches, 
and the deflection -^^^ of an inch to the foot, when uniformly loaded 
with the weights in this table. 
WEIGHT IN 
POUNDS UPON EACH 
FOOT 
IN LENGTH. 
Length 
'clear ' 
15-62 
20-79 
27-00 
34-32 
42-87 
52-73 
64-00 
76-76 
91-12 
107-17 
bearing. 
DEPTH IN INCHES. 
1 
2 
3 
4 
5 
•37 
•75 
112 
1^50 
1-87 
-41 
•82 
1-23 
1-65 
2^06 
•45 
•90 
V35 
1- 80 
2- 25 
-49 
•97 
1-46 
1- 95 
2- 43 
-52 
1-05 
1- 57 
2- 10 
2-62 
•56 
M2 
1- 68 
2- 25 
2-81 
•60 
1-20 
1- 80 
2- 39 
2-99 
•64 
1-27 
1- 91 
2- 54 
3- 18 
•67 
1- 35 
202 
2- 69 
3- 37 
•71 
1^42 
213 
2^84 
3-55 
7 
8 
9 
10 
2-25 
2-62 
2- 99 
3- 37 
3-74 
2-47 
2- 88 
3- 29 
3- 70 
4- 12 
"¥69 
3^14 
3^59 
4^04 
4-49 
2- 92 
3- 41 
3- 89 
4- 38 
4-86 
3-14 
3- 67 
4- 19 
4- 71 
5- 24 
3-37 
3- 93 
4- 49 
5- 05 
5-61 
3- 59 
4- 19 
4- 79 
5- 39 
5-99 
3- 82 
4- 45 
5- 10 
5- 73 
6- 36 
4-04 
4^71 
5^39 
6^06 
6-74 
~4-27 
4- 98 
5- 69 
6- 40 
7- 11 
11 
12 
13 
14 
15 
4-12 
4-49 
4- 86 
5- 24 
5^61 
4-53 
4- 94 
5- 35 
5- 76 
6- 17 
4- 94 
5- 39 
5- 84 
6- 29 
6-74 
5-35 
5- 84 
6- 32 
6- 81 
7- 30 
'¥76 
6-29 
6- 81 
7- 33 
7-86 
6- 17 
6^74 
7- 30 
7- 86 
8- 42 
6- 69 
7- 18 
7- 78 
8- 38 
8-98 
7-01 
7- 63 
8- 27 
8- 91 
9- 54 
7^41 
8^08 
8- 76 
9- 43 
10-10 
7- 82 
8- 53 
9- 24 
9-95 
10-66 
16 
17 
18 
19 
20 
5- 99 
6- 36 
6- 74 
7- 12 
7-48 
6- 59 
7- 00 
7-41 
7- 82 
8- 23 
7-18 
7- 63 
8- 08 
8-53 
8-98 
7- 78 
8- 27 
8- 76 
9- 24 
9-73 
8-38 
8- 91 
9- 43 
9-95 
10-48 
8- 98 
9- 54 
10-10 
10- 66 
11- 23 
9-58 
10-18 
10- 78 
11- 38 
11-97 
10-18 
10- 81 
11- 45 
12- 09 
12-72 
10- 78 
11- 45 
12- 12 
12- 80 
13- 47 
11- 38 
12- 09 
12- 80 
13- 51 
14- 22 
Multipliers to give the breaking weight of every Scautling in each column respectively. 
14-05 
12-77 
11-70 
10-80 
10-03 
9-36 
8-78 
8-26 
7-80 
7-39 
*^* The weight of Slating, including the force of the wind, may be estimated at 56 lbs., 
and that of Tiling, at 62 ibs. per superficial foot. 
* Example. — If the Rafters for a slated roof be 15 inches apart from middle to middle, 
the pressure upon each foot in length is 56 x l'//3" = 70 fbs. A Rafter 6 feet long, 3-82 in. 
by 1| in., with 7676 lbs. weight to the foot, deflects in the middle -A. of an inch; and the 
breaking weight of the same is 6 x 76'76 x 8-26 = 3804 ibs., the pressm'e being uniform, and 
at right angles to the plane of the roof. 
