24 BULLETIN 23, tf. S. DEPARTMENT OF AGRICULTURE. 
than 300 pounds. When finished it shall present a smooth, uniform 
appearance. 
The brick. — The brick shall be delivered upon the road and neatly 
piled outside of the curb lines at such points as are approved by the 
engineer before the grading is started. The loading, hauling, and 
unloading shall be carefully done, and at no time shall the brick be 
thrown, dumped, or in any way roughly handled. 
All brick used in the pavement shall be thoroughly vitrified, regular 
in shape and size, evenly burned, and first class in all other respects. 
The dimensions shall be 3^ inches in width, 4 inches in depth, and 
8^ inches in length, and any brick varying from these dimensions 
by more than one-half inch in length or by more than one-eighth 
inch in width or depth shall be rejected. If the edges are rounded, 
the radius of the curve shall not exceed one-eighth inch. Each brick 
shall have projections on one side, formed during the process of 
manufacture, which will serve to produce joints not exceeding one- 
fourth inch in width and not less than one-eighth inch, when the 
brick are placed in the pavement. 
No brick shall be used in which representative specimens, when 
subjected to the rattler test recommended by the subcommittee on 
paving brick of the American Society for Testing Materials * lose 
more than 22 per cent of the original weight of the dried brick com- 
posing the charge. In making this test 10 representative bricks shall 
constitute a charge and, in weighing the rattled brick, no part of a 
brick weighing less than 1 pound shall be included. 
The modulus of rupture for any one representative brick shall not 
be less than 2,400, and the average modulus of rupture for all bricks 
tested shall not be less than 2,600. If this test is employed, at least 
five bricks shall be tested. 
Any carload of brick more than 10 per cent of which fails to con- 
form to any of the above requirements shall be rejected. If not more 
than 10 per cent of a carload fails to meet the requirements, the 
defective bricks may be picked out and the remainder of the carload 
used. 
Laying the brick. — The brick shall preferably be carried to the 
pavers on pallets or in clamps and not wheeled in barrows. They 
shall be laid in straight courses at right angles to the line of the pave- 
ment, and if a variation in alignment of more than one one-hundred- 
and-twentieth the width of the pavement occurs, it shall be corrected 
by taking up and relaying affected courses. 
Xo parts of brick shall be employed in the pavement except at the 
beginning and ending of the courses or at other closures. All brick 
shall be laid with the best edge exposed and as close as possible. 
After the brick are laid, they shall be carefully inspected and all those 
1 The complete specifications for making this test are given as an appendix to this bulletin. 
