CONSTRUCTION AND FIRE PROTECTION OF COTTON WAREHOUSES. 21 



storage compartment, though openings frequently are necessary in 

 compress compartments to connect them, or to connect the compress 

 with the adjacent storage compartment. In any easel the opening 

 should be as small as is practicable and should conform to the limi- 

 tations stated later in the discussion of the doors themselves. Con- 

 struction and design of fire doors is discussed in detail later.^ 



Mf brick ifi used tboy sliould bo well burned and at least two-tbirds of them 

 hard (or fully burned), tlie "run-of-kiln guaranteed two-thirds hard" being 

 satisfactory'. Care should be taken to see that extremely soft brick from the 

 outside of the kiln are thrown out. The hardei^ brick of the lot should be 

 used for the exposed surfaces of the wall, and the softer brick used for filling 

 in between. 



The brick should be laid fairly close together with joints well filled with 

 mortar. Ample "bond" or "header" courses should be used to tie the parts 

 of the wall firmly together, this tie being used for every sixth course. The 

 work should not be carried on in freezing weather, while if the weather i3 

 warm and dry the brick should be wet before they are laid, as this prevents 

 too rapid drying of the mortar. The mortar used for the fire wall preferably 

 shouki contain a mixture of one part Portland cement, one-seventh part lime 

 (either putty or hydrated), and sand not exceeding three parts, and should 

 be mixed only as required for use. A fairly satisfactory mortar for use above 

 the ground, however, may contain one part Portland cement, one part lime 

 (either putty or hydrated) and six parts sand. Cement should not be added 

 more than one-half hour in advance of use of the mortar. 



When concrete is used, it should be prepared under competent supervision, 

 while the actual work can be done largely by unskilled labor. Mixing and 

 casting should not be done in freezing weather. Concrete not reinforced with 

 steel should contain one part of Portland cement, two and a half or 3 parts 

 sand, and five parts of suitable gravel or crushed stone. The chief dangers 

 to be guarded against are leakage of the form in which casting is done, 

 insufficient mixing, and careless packing or tamping. Concrete reinforced with 

 steel, as used for walls, should conform to the requirements later stated in 

 reference to " Reinforced concrete." The top of the opening should be formed 

 by .a substantial brick arch or a concrete lintel. Steel or iron lintels may be 

 used provided they are protected by either 4 inches of brickwork or a com- 

 plete overlapping of the door. The threshold should be of iron or steel, se- 

 curely anchored, or the sill (including the part against which the door closes) 

 may be of concrete 6 inches or 9 inches thick and fully supported by the wall. 

 An example of 4 by 4 inch steel angles used with concrete is shown by Plate 

 XIV, figure 5. A solid cast-iron threshold with the surface roughened is to be 

 preferred. The threshold should be raised l"!^ inches or 2 inches, with the floor 

 sloped up to this level, so that water used to extinguish fire in one comi^art- 

 ment will not flow into the one adjoining. 



Vestibule doorways afEord excellent protection of the oi>eniug. An example 

 of such an arrangement is shown by Plate XIV, figure 6, where the low story 

 makes the arrangement sho'mi fairly economical. Where the stoiy is very high 

 the vestibule may be constructed with a low ceiling covering slab. The width 

 of the vestibule "corresponds to the width of doors, while for the depth, or dis- 

 tance provided between the doors, 6 feet is sufficient unless it is desired to use 

 one ST^-iuing door opening into the vestibule, as is shown by the drawing. In 

 such sase the minimum distance of G feet would be increased to suit the width 

 of door used. 



