178 



VETERINARY HYGIENE 



FIG. 77. Section of a piggery. The dotted lines above the pen partitions 

 indicate the height to which the partitions should be built for a boar's pen. 

 An alternative method of providing outlet for the foul air is by a per- 

 manently open ridge as shown in the adjoined figure, in which case the 

 Sherringham windows are used instead of fireclay pipes for the air inlet. 



FIG. 78. Plan of the above piggery. 



