INFORMAL RAISED HEARTH TYPE 



ADAPTATION TO LOCATION AND USE 



This type has the same problems concerning 

 adaptations to location and to use as relate to 



the fireplace shown in plate VI. 



DESIGN AND CONSTRUCTION 



The slabs of stone on which to set cooking 

 utensils, and related to the fireplace as indi- 

 cated in the sketch, have a tendency to more 

 directly "tie" this feature to the ground. The 

 single capstone across the back of the fireplace 

 extends over and is set flush with the face of the 

 fire-clay brick lining in order to improve the 

 design and the construction. The front corners 

 of the fireplace are returned in such a manner 

 that they partially conceal the fire-clay brick 

 Uning. 



The hearth if raised to a height approxi- 

 mately 12 inches above the ground level, would 

 bring the cooking surface at the top of the 

 grate or plate to a height of 22 inches, which 

 wovild make the unit more convenient for camp 

 use, and more massive. 



This entire structure (excepting the single 

 slabs of rock at either side) should rest upon a 

 reenforced concrete floating pad foundation. 

 The flanking rocks are buried slightly in the 

 ground. 



The hearth should be constructed of fire-clay 

 brick laid on a masonry fill on top of the con- 



crete foundation. There may or may not be a 

 projecting stone hearth at the front of the fire- 

 place. 



The fire-clay brick is anchored by the cap 

 stone across the back and is carried only to 

 the level of the stone masonry wall on the sides. 

 In this method of construction, the joint between 

 the fire-clay brick and the stonework should be 

 very carefully constructed in order to avoid the 

 possibility of water entering between the fire- 

 clay brick and the stonework, thus causing 

 damage during the winter months. 



The success of this fireplace depends upon 

 the use of large units of stone of a uniform char- 

 acter, and upon a careful treatment of the 

 joints in order to conceal them as much as 

 possible. The flanking rocks which are not set 

 upon any foundation should be entirely free 

 from the fireplace structure, so that in heaving 

 and settling under frost action no damage will 

 be done to the stone masonry. 



VARIATION IN DESIGN 



A variation (figs. 2 and 6) indicates the hearth 

 lowered to the ground level with the fire-clay 

 brick in the hearth omitted, and sand or min- 

 eral earth substituted in its place. In this varia- 

 tion in design the foundations under the side 

 and rear walls should be carried below the 

 frost line. 



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