136 VETERINARY HYGIENE 



The use of linoleum on wooden floors situated near the ground 

 is a frequent cause of the growth of dry rot. 



CONSTRUCTION OF WALLS. 



The walling of a building should be looked upon primarily as 

 a shelter from cold wind and rain. Its secondary duty is to support 

 any upper floor and the roof as well as to form a support for stall 

 divisions and stable or byre fittings. 



It is obvious that a wall must not readily absorb moisture either 

 from driving rain or by capillary attraction from the soil. The 

 preliminary to building a wall of any description is to excavate a 

 foundation track of the depth necessary to remove all top soil and 

 humus, down to a bed of firm clay, sand, gravel, blaes or rock. The 

 formation should be levelled or stepped into level stretches. For 

 concrete foundations the track should be of the exact width of the 

 concrete. The thickness and width of a foundation will depend 

 upon the nature of the soil, but it is a good rule to make the thick- 

 ness never less than 9 inches, and preferably 12 inches thick for 

 the usual farm building. The width of a foundation may be from 

 9 inches to 12 inches more on each side than the thickness of the 

 wall to give the necessary bearing area upon the soil. If concrete 

 foundations are not used, which is rarely the case to-day, a founda- 

 tion may be constructed in brickwork by forming scarcements. 

 These are a stepped increase in the thickness of the wall, greatest 

 at the base. They are open to objection, as being full of joints 

 they give more readily than concrete to any soft part of the soil 

 and cause a settlement in the building. Brick footings tend to draw 

 moisture from the soil. Concrete foundations are always to be 

 recommended as they are monolithic, resist the passage of moisture 

 and are strong. Sometimes brick footings are built on a concrete 

 foundation as shown in figure 91. 



Upon the foundation, the top of which should be level, the wall 

 is built and brought up all round the structure to a level surface 

 to receive the damp-proof course about 4 inches above the ground 

 level. In this case the stable or byre floor would be 2 inches above 

 the damp-proof course, making the floor 6 inches above the ground 

 if the site is level. The damp-proof course is important and must 

 be executed with care. For details of construction refer to the 

 section " Dampness in Buildings and its Prevention." 



The material of which a wall is built depends upon the geo- 

 logical formations of the district. Brick walling is possible in 

 most localities and is suitable, being regular in structure, smoother 



