16 BULLETIN 373, U. S. DEPARTMENT OF AGRICULTURE. 
cement to five parts of sand is probably the most usual proportion. 
The mixing is generally done in a mechanical mixer, and the material 
is spread and compacted just in advance of the brick layers. It is 
of course essential that the bedding be kept dry until after the brick 
are laid. 
HANDLING AND LAYING THE BRICK. 
The. brick may all be hauled and piled at convenient intervals 
along the sides of the roadway before grading is begun, or, if more 
convenient, they may be delivered as needed on the work. Hauling 
over the finished pavement with wagons until it is complete and 
opened to traffic should be avoided. If the brick are delivered on the 
work as needed, they should be unloaded from the wagons outside of 
the curb and carried to the pavers, either by hand or in wheelbar- 
rows. Plank trackways should also be provided over the newly laid 
pavement for the wheelbarrows when they are used. 
The brick should in all cases be uniformly piled by hand on the new 
pavement conveniently close for the pavers, and each brick should be 
so placed that the regular operation of picking it up and placing it in 
the pavement will bring the best edge up. This method of handling 
the brick requires somewhat more labor than the common method of 
dumping them from wheelbarrows, but it eliminates to a great extent 
the practice of picking out and turning over chipped or kiln-marked 
brick after the pavement is laid. This is very objectionable on ac- 
count of the disarrangement of the sand cushion, which is frequently 
occasioned. 
The brick should be laid on edge and in uniform courses, running 
at right angles to the line of the pavement, except at intersections; 
and in order to " break the joints " each alternate course should begin 
with a half brick. In laying the brick the pavers stand on the pave- 
ment already laid and, be ning at the curb each time, carry across 
as many courses together as they can conveniently reach. The courses 
should be kept straight and close together, and, if necessary, each 
block of 8 or 10 courses may be driven back by means of a light 
sledge and a piece of straight timber approximately 2 by 4 inches by 
5 or 6 feet long, though no heavy driving should be permitted. The 
brick should also be laid close together in the courses. 
After the brick are laid the pavement should be carefully inspected, 
for the purpose of detecting soft or otherwise defective brick. Mis- 
shapen or broken brick may be detected by the eye alone, and the soft 
brick by sprinkling the pavement with water. The soft brick appear 
comparatively dry while the water is being applied and compara- 
tively wet after the sprinkling is stopped. All defecth^e brick should 
of course be replaced by others which meet the requirements of the 
specifications. 
