4 BULLETIN 801, TJ. S. DEPARTMENT OF- AGRICULTURE. 
exposed walls and frame construction for the walls not exposed. 
In the case of a number of parallel buildings with courts between 
only one exterior side wall of each entire building may be masonry. 
Such an arrangement is good but is not nearly so satisfactory as 
when all walls are masonry. 
Slow-burning construction is illustrated by the photograph of a 
warehouse of three-story design in Plate III, figure 2. This build- 
ing has floors and roof of timbers and heavy planking, exterior 
and division walls of brick, with tin-clad fire doors throughout. 
The platform is of reinforced concrete which requires practically 
no repairs and does not communicate fire. In this building the 
story height is only 8^ feet and cotton is stored one bale high on 
end. Such buildings should not exceed three stories in height un- 
less there are floors of reinforced concrete to serve as fire breaks. 
The type of exterior door used in this building is shown by Plate 
XIII. figure 2. 
A similar building, well suited to conditions which demand con- 
centration or where the area is limited, is shown in Plate IV, figure 1. 
For buildings of this design it is best that all floors be fire-resistive. 
The fire-resistive floor has the advantage of limiting the amount 
of cotton subject to a single fire and, what is more important, it 
serves as a tie to the walls and prevents their subjection to such 
severe and prolonged heat as to cause their failure from expansion. 
For such buildings the automatic sprinkler equipment is practically 
essential, while the installation of stand-pipes with hose equipment 
on each platform is of great importance. A view of such a stand- 
pipe and hose equipment is shown in Plate XXXII, It usually 
is not necessary to have platforms on both sides of the building, 
but if platforms are omitted on one side, doors of sufficient number 
and size should be provided on that side to permit of cotton being 
thrown out and, more important, to admit of ready access by 
firemen. These features of construction are illustrated by Plate IV, 
figure 2. In this view the minimum number of doors advisable 
is shown. If any floors in the building are fire resistive, or if the 
exterior exposure is hazardous, doors should be covered with tin 
as described for fire doors under " Fire-resistive construction," or 
should be otherwise equivalent to fire doors. The iron ladder gives 
ready access to the doors. 
Fire-resistive construction for the warehouse does not involve 
any radical departure in design from the slow-burning construction 
described. The difference is that all floors and roof are of fire- 
resistive material, such as reinforced concrete, and that openings 
are fully protected' as required by their location and exposure. 
The construction of the floors and other features are discussed 
under " Fire-resistive construction." An interior view of such a 
