62 NEW YORK STATE MUSEUM 



to drying. Lugs are a necessity on paving bricks and are either 

 formed by the process of repressing or at the time of cutting. 



" The product now goes to the drying tunnels where a temperature 

 sufficient to dry the bricks in about 24 hours is secured either by 

 the use of steam, waste heat from the kilns, or by direct heat. The 

 bricks lose in moisture about 20 per cent of their original weight in 

 the process of drying. The cars have a capacity of from 450 to 

 500 bricks and traverse a distance of about 100 feet between the 

 time of entering and leaving the drying tunnels. 



" Burning, which is probably the most important branch of the 

 industry, is carried on in down-draft or in continuous kilns, using 

 bituminous or anthracite coal with or without a forced draft. Kilns 

 and methods of burning vary. The kiln in most common use, 

 known as the rectangular down-draft kiln, has inside dimensions 

 of about 80 feet in length by 18 feet in width and 12I feet in height 

 with ten or more fireplaces on each side. The fireplaces are built 

 in such a manner that the heat reaches the top of the kiln first, 

 passes down through the green brick, then through the floor and by 

 a system of flues to the stack. The proper bum is recognized almost 

 entirely by the settle of the brick. Kilns are set about 27 bricks 

 high, the bricks separated from each other by a thin layer of sea 

 sand, and burned from 10 to 12 days until the material settles from 

 12 to 15 inches. On account of the difference in kiln temperature 

 between the top and bottom it is the usual custom to set the first 

 two to six layers with either common, side- walk, or rough -faced 

 front brick that do not require so high a temperature to bum as do 

 the paving brick. 



" A circular down-draft kiln is also used in the burning of paving 

 brick. The kiln, in this case, has an inside diameter of from 20 

 to 30 feet and a height of about 14 feet, and is usually furnished 

 with eight fireplaces having individual stacks or all drawing to one 

 stack. It would seem from experience that the circular down-draft 

 kiln has some advantages in temperature regulation. The continuous 

 kiln in use for the burning of paving brick, in this State at present, 

 is of the Haight type. This consists in form of two rectangular 

 kilns placed in a parallel position and connected at both ends by a 

 semicircular extension of the same cross section. The kiln is 

 divided into fifty-five chambers and after the original fire is started 

 it is a continuous operation of setting, burning, cooling and emptying. 

 This kiln is top fired, using bituminous coal, the fire being controlled 

 and regulated by dampers. The waste heat in cooling is carried 

 over to a forward chamber and assists in drying. As soon as a 



